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I am super excited to announce a new edition of our GMAT Advanced Quant Strategy Guide! We worked hard on this book all of last year (yes, it takes a long time make a book!) and we hope that you find it to be a valuable addition to your GMAT preparation.

What is the Advanced Quant guide? We created the Advanced Quant (AQ) guide a few years ago for people who want to get a top score (50 or 51) on the quant section of the GMAT.

Here’s the interesting thing: it doesn’t teach you a bunch of really hard math concepts. We teach all of those concepts in our five regular strategy guides (Algebra, Geometry, Word Problems, Number Properties, and Fractions, Decimals, & Percents). Instead, the AQ guide teaches you the next level of GMAT study: how to think your way through really hard quant problems.

What’s new in this edition? A bunch of things! First, there are more than 50 brand-new, extremely hard problems. We actually removed some old ones that we thought were a bit too easy and replaced them with harder problems.

But that’s not all. Since the entire point of this book is how to solve better, we’ve updated some solutions to existing problems because we’ve discovered an even more efficient or effective way to solve.

We’ve also introduced a new organization method for working your way systematically through any quant problem. We’ve added or expanded lessons on test-taking strategies, such as testing cases on both problem solving and data sufficiency problems.

One student, who has already used the old version of AQ, asked whether we would provide a list indicating which questions are the new ones. I told him no. Not because I’m lazy or I don’t care, but because you don’t need such a list! If you’ve already tried the first edition and want to try this one, too, just start going through the book. If you hit a problem you remember, feel free to skip it. (Although maybe this is a chance to see if you really do remember what to do…and remember that we may offer an updated solution that you haven’t seen before.) If you hit a problem you don’t remember, then it doesn’t matter whether it’s old or new. It’s new to you right at this moment!

Who should use the AQ Strategy Guide? First, you should have mastered most (if not all) of the material in our five main quant Strategy Guides. As I mentioned earlier, we do not actually teach you that math in this guide. We assume that you already know it.

As a general rule, we recommend that people avoid using this book until they’ve gotten to a score of at least 47 on a practice CAT. (Seriously. We say so right in the first chapter of the book!) I might let that slide a bit for certain students, but someone scoring below 45 likely does not have the underlying content knowledge needed to make the best use of the Advanced Quant lessons.

Note that, from an admissions standpoint, you may not necessarily need to score higher than 47. The scoring scale tops out at 51, so 47 is already quite high. Do a little research to see what you may need for the specific schools to which you plan to apply.

All right, that’s all I’ve got for you today. I’d love to hear what you think about the book. Which problem is your favorite? And which one do you think is the absolute hardest, most evil thing we could have given you? Let us know in the comments!

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The new Official Guide books are here! Aren’t you excited?!?

Okay, I realize that most people probably aren’t as excited as I am. But there are still some interesting and useful things to know about these new books as you get ready to take the GMAT. So let’s talk about it!

In this installment, I’ll discuss additions and changes to quant sections for The Official Guide for GMAT® Review 2016, aka the OG or the big book. Keep an eye out for later installments, in which I’ll discuss the verbal section of the big book, as well as the Quantitative Review and Verbal Review books. I’ll also be providing you with a list of the new questions, in case you decide to study from both the 2015 and 2016 editions.

If you haven’t already bought your official guide books, then do buy these latest editions—sure you might be able to get a discount on the 2015 editions, but since you have to spend money anyway, you might as well work from the latest and greatest.

If you have already bought the older editions and are debating whether to buy the new ones, too, then you’ve got a decision to make. On the one hand, there are a lot of great new questions in the 2016 editions. On the other, the 2015 edition already has a ton of problems; you may not need even more. If it were me, I’d wait until I’d used up the ones in the materials I already have. If I still felt that I needed more beyond that, then I’d consider getting one or more of the new books.

What’s new in OG 2016? Approximately 25% of the questions are brand new, and there are some beauties in the mix. As I worked through the problems, I marveled anew at the skill with which the test writers can produce what I call elegant problems. On the quant side, I saw example after example in which the problem can be solved with little to no computation as long as you can decode and understand the fundamental concept underlying the problem—that’s the real test-taking skill!

Rich D’Amato, spokesperson for GMAT, confirmed that a decent number of the new questions were produced relatively recently; that is, you’ll be seeing questions that were on the real exam not too long ago. (The older questions are still great study questions, too; the GMAT is a standardized test so, by definition, the test makers can’t change things too drastically or rapidly. There can be some mild trends over time, though. For example, the test makers may decide that certain idioms should be retired from or introduced for Sentence Correction problems.)

The opening chapters of the book describe how the GMAT works and how to study for the test; these sections have not changed. Nor has the Math Review (chapter 4). This is no surprise—again, the GMAT is a standardized test and, as such, it remains very consistent over time. The Diagnostic test in chapter 3 also has not changed.

What’s new in Quant? Overall, I noticed multiple new problems that crossed two or (occasionally) even three content areas. For instance, #18 is a geometry question that also crosses into percents, as does overlapping sets Problem #91. I chose those two examples on purpose so that I could also point this out: fractions and percents, in particular, are really good concepts to cross over into any other content area, so make sure you have a very solid foundation in both fractions and percents.

I also noticed a few visual questions—a couple of 3-D geometry and some coordinate plane problems that were made much harder by my general tendency to struggle with this kind of visual stuff. If you’re like me, beware; you may decide ahead of time that you want to bail immediately on 3-D or other problems that have a heavy visual component.

Problem Solving

Of the 230 questions in the Problem Solving (PS) section, 58 of them are new. (Disclaimer: I hope I counted correctly for all of these sections, but I’ve been going through about 1,500 questions and hundreds of pages quickly in order to get this review out to you right away. So please forgive me if I miscounted anything! I’ll correct any errors as soon as I find out about them.)

I noticed a number of what I’ll call “practical” questions: the question, usually a story problem, reads like something you might be asked to figure out in the real world. Problem #11, for example, asks you to figure out the minimum number of questionnaires you’d need to mail in order to achieve a certain desired number of responses. (The problem includes an assumed response rate.)

Note: I can’t actually reproduce the text of the question for copyright reasons, but I’m citing the problem number so that you can look it up if you do decide to buy the book.

Problem #39 can literally be counted out on your fingers—as long as you understand what you’re being asked to do. Be careful with definitions!

I also saw several problems that seriously disguised what the question was getting at. I don’t want to spoil you for the questions—better if you can figure it out for yourself!—but take a close look at #68 and #83. On the surface, these would be classified as algebra. But at least one can be done more easily using a different set of concepts. (I’ll tell you at the end of this article. But don’t look until you’ve tried to figure it out yourself!)

I used smart numbers to solve a number of the problems and I also worked backwards multiple times. In other words, these strategies are just as important as they always were. I did notice one question (#99) on which we could use smart numbers but the form of the answers indicated that it’d almost certainly be easier to do algebra. Look at the problem; you’ll see what I mean!

Finally, let’s talk about those elegant questions. If you can understand the concepts underlying #97, then you barely need to calculate anything at all—even though it looks as though you’re going to need to do some annoying algebra to answer the problem. Likewise, #107 has a huge disguise that, once uncovered, allows you to answer in two seconds without calculating anything at all. (Again, I’ll tell you what this is at the end of this article.)

Data Sufficiency

Of the 174 Data Sufficiency (DS) problems, 45 are new to this edition of the OG.

Continuing on the theme from PS, I was really struck by the number of new story problems for which translation is the whole key. If you translate carefully and accurately, then you don’t need to do anything more to solve. For example, #38 looks particularly nasty. Translate that thing very carefully, though, and you won’t have to do any messy calculations to answer. Problem #83 is another example; the story is pretty confusing, but if you can lay out the parts carefully and clearly, then the rest of the problem is more about logic than math.

Next, I used testing cases numerous times; as with PS, the standard test-taking strategies are still in full evidence on DS. I also noticed that, as before, it’s crucial to make sure you know what you were asked to find. This is true on PS too, of course, but DS tends to set more traps around solving for the wrong thing. Check out #39. You can’t find t by itself, but you can find t2, and that’s good enough to solve.

So what were all those cool disguises and tricks you mentioned? Here you go. Again, do not read this until you have worked on these problems yourself! If you can figure out what’s going on yourself, the lesson will stick much better in the end. J

PS #68 and #83. These two problems share a consecutive integer disguise. The givens can be read to mean consecutive integers (the second one has to be rearranged to do so) and, since in each case the two terms multiply to an integer, that tells you that you’re dealing with the factors of that integer. For instance, in #68, the factors of 24 are (1, 24), (2, 12), (3, 8), and (4, 6). BUT note that the problem does not actually mention factors or specify positive numbers, so you also have to take into account that the pairs could be negative.

Next, you know that they have to be consecutive odds or consecutive evens, so the only two pairs that work are (4, 6) and (-4, -6). From there, you can figure out the answer. Problem #83 has a similar disguise, although it can also be solved via quadratic equations.

PS #97. The question asks you to maximize the depth, N(t). The -20(t – 5)2 term has that negative sign out front, so it could reduce the depth, so you need to minimize the negative value. How? Make the (t – 5) term equal to zero!

PS #107. I love this one. It’s a weighted average question in disguise. The formula x + y = 1 signifies that the two weightings add up to 100%: x + y = 100%, where x and y are the two weightings. The formula 100x + 200y signifies the weightings that you’re applying to each of the two endpoints, 100 and 200. The weighted average must be somewhere between the two starting numbers / endpoints, so only two of the roman numerals can work.

DS #38. The question tells you to set (1/12 + kv2) equal to 5/12. Then it asks you for v. If you know k, then you can find v. So the real question is whether the statement allows you to find k. Statement (1) obviously does, and statement (2) also does, because it gives you another equation: (1/12) + k(30)2 = 1/6.

DS #83. There are x processors. Each processor can process up to y calls. Think about what this means—maybe even draw a picture. Note that x has to be at least 1 and y has to be at least 1. If you have x = 1 processor that can process y = 500 calls, then sure, you can process 500 calls at once. If you have x = 10 processors that can process y = 10 calls each, then nope, you can’t process 500 calls at once.

So you need to know something about x and y in order to answer. It looks, then, like statements (1) and (2) can’t work alone, since each talks about only one variable. But don’t forget the constraint that each has to be at least 1!! If you have x = 600 processors, then you can definitely process 500 calls, since each processor has to be able to process at least one call.

What about Verbal? And the other books? Next time, we’ll dive into the verbal sections of the Big OG. Then, we’ll discuss the quant and verbal supplements, and finally, I’ll provide you with lists of the new questions in each book and also the new question numbers for the old questions that remain in the book from the last edition.

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(Note: I have not yet had time to analyze the IR problems that come via your special online access. I’ll get to that soon—the quant and the verbal are higher priority!)

Part 1 included an overview of the changes to the whole book; I’ve included that overview here as well (the next section!), in case you’re reading this installment first. (The only difference is one sentence in the first paragraph.)

What’s new in OG 2016? Approximately 25% of the questions are brand new, and there are some beauties in the mix. As I worked through the problems, I marveled anew at the skill with which the test writers can produce what I call elegant problems. On the verbal side, I loved how some of the new questions wove meaning into the issue of Sentence Correction; if you have been focusing on grammar and shortchanging meaning, you’re definitely going to need to change your approach.

Rich D’Amato, spokesperson for GMAT, confirmed that a decent number of the new questions were produced relatively recently; that is, you’ll be seeing questions that were on the real exam not too long ago. (The older questions are still great study questions, too; the GMAT is a standardized test so, by definition, the test makers can’t change things too drastically or rapidly. There can be some mild trends over time, though. For example, the test makers may decide that certain idioms should be retired from or introduced for Sentence Correction problems.)

The opening chapters of the book describe how the GMAT works and how to study for the test; these sections have not changed. Nor has the Math Review (chapter 4). This is no surprise—again, the GMAT is a standardized test and, as such, it remains very consistent over time. The Diagnostic test in chapter 3 also has not changed.

What’s new in SC? Of the 140 questions in the Sentence Correction (SC) chapter, 35 are new. Sentence Correction is always difficult to classify because one question can test multiple different topics, and one difference can straddle the line between two topics. A full 16 of the new questions, though, test meaning or sentence structure (or both). I thought that there were some interesting sentence structure examples; keep an eye out for my eventual problem lists, in which I’ll add notes about things that caught my eye when doing the problems.

When comparing the questions that were dropped to the ones that were added, meaning definitely jumped in the count. This is again a judgment call: when do we classify something as pure meaning vs. a grammar error that messes up meaning? But using a consistent standard across all of the questions, I counted 10 new meaning SCs compared to 3 dropped.

All of the other categories didn’t change substantially (not a big surprise, since this is a standardized test). I do want to point out that 19 out of the 35 new questions cover parallelism or comparisons. In other words, these two topics were important before and they still are. Study them!

What’s new in CR? Of the 130 questions in the Critical Reasoning (CR) chapter, 35 are new.

When comparing the number of questions dropped vs. added, it was the case that Strengthen questions jumped a bit, while Weaken and Inference dropped a bit. These trends also appeared in the Verbal supplement, so I’m noting them here, though I also want to add that the numbers are small enough that we can’t say definitively that they reflect any kind of change in the test. (Also, there were some other seeming trends that didn’t actually hold for both books, so I’m ignoring those.)

All of the questions except for one (#39) fit neatly into our existing classification categories. I’m still trying to decide how I would classify #39. It’s in the Assumption Family but I keep going back and forth on whether I would call it a Strengthen or a Weaken. The question stem alone is most like a weaken (an “alternative explanation” would be like saying “Hey, here’s a better conclusion than the one you came up with!”). But the reasoning for the correct answer choice can be interpreted as a Strengthen. I’m going to be asking some fellow teachers, and even GMAC, about this one; I’ll get back to you.

What’s new in RC? We lost 3 shorter and 3 longer passages from the 2015 edition; 3 of these were social science, 2 were science, and 1 was business.

We gained 4 longer passages and 2 shorter ones; 4 of these were science and 2 were social science. I’m not sure whether that indicates any kind of increased emphasis on science topics, but it’s certainly interesting that not one of the new passages is a business passage.

There are 31 new questions total out of 139 questions total. 15 specific detail question were dropped and only 7 were added. That 8-question differential was added to specific purpose (why) questions (+5), weaken (+2), and main idea (+1). The latter two are pretty small changes, but I found it very interesting that 5 why questions were added.

What else? Tell me more! I’ve got more for you! In later installments, we’ll talk about the Quant Review and Verbal Review (the smaller OGs) and I’ll give you lists of the new question numbers as well as the updated question numbers for the problems that are in both books. Until then, happy studying!

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I have now done every last one of the new quant problems in both new books—and there are some really neat ones! I’ve also got some interesting observations for you. (If you haven’t yet read my earlier installments, start here.)

In this installment, I’ll discuss my overall conclusions for quant and I’ll also give you all of the problem numbers for the new problems in both the big OG and the smaller quant-only OG.

What’s new in Quant? Now that I’ve seen everything, I’ve been able to spot some trends across all of the added and dropped questions. For example, across both The Official Guide for GMAT® Review (aka the big book) and The Official Guide for GMAT® Quant Review (aka quant-only or the quant supplement), Linear Equation problems dropped by a count of 13. This is the differential: new questions minus dropped questions.

That’s a pretty big number; the next closest categories, Inequalities and Rates & Work, dropped by 5 questions each. I’m not convinced that a drop of 5 is at all significant, but I decided that was a safe place to stop the “Hmm, that’s interesting!” count.

Now, a caveat: there are sometimes judgment calls to make in classifying problems. Certain problems cross multiple content areas, so we do our best to pick the topic area that is most essential in solving that problem. But that 13 still stands out.

The biggest jump came from Formulas, with 10 added questions across both sources. This category includes sequences and functions; just straight translation or linear equations would go into those respective categories, not formulas. Positive & Negative questions jumped by 7, weighted average jumped by 6, and coordinate plane jumped by 5.

Given that Linear Equations dropped and Formulas jumped, could it be the case that they are going after somewhat more complex algebra now? That’s certainly possible. I didn’t feel as though the new formula questions were super hard though. It felt more as though they were testing whether you could follow directions. If I give you a weird formula with specific definitions and instructions, can you interpret correctly and manipulate accordingly?

If you think about it, work is a lot more like this than “Oh, here are two linear equations; can you solve for x?” So it makes sense that they would want to emphasize questions of a more practical nature.

Anything interesting about the new questions? In an earlier installment, I told you about some interesting problems from the big book. Here are a few more observations from the Quant-only supplemental book.

Problem Solving

Of the 176 questions in the Problem Solving (PS) section, 44 of them are new. (Disclaimer: I hope I counted correctly for all of these sections, but I’ve been going through about 1,500 questions and hundreds of pages quickly in order to get this review out to you right away. So please forgive me if I miscounted anything! I’ll correct any errors as soon as I find out about them.)

Note: I can’t actually reproduce the text of the question for copyright reasons, but I’ll cite the problem number so that you can look it up if you do decide to buy the book.

A number of questions relied on some type of pattern recognition: #125, #143, #161. They’re not interested in you doing crazy math. They’re interested in whether you can recognize patterns and draw some kind of meaningful conclusion.

In my notes, I labeled #80 “Wow. That’s just mean.” And #152 got a “Pure evil” tag. (#152 requires mental manipulation of a 3-D shape and that’s just not something I have ever been able to do.)

I’d far rather work backwards on #127 than do the actual math. Others may feel differently, but the textbook math on this one is pretty annoying.

Data Sufficiency

Of the 124 Data Sufficiency (DS) problems, 32 are new to this edition of the Quant OG. There were some doozies.

I couldn’t believe #124, the highest numbered question in the section: a parabola inequality (not even an equation!). Now, if you like geometry, great—learn how to tackle parabolas. If you don’t, then if you happen to get one of these on the real test, give yourself a mental high five for earning this question, then pick your favorite letter and move on!

I almost fell into the trap on #123. I’m so used to rate and work questions specifying that whatever was moving at a steady rate that I almost didn’t notice the omission in this one…

Also, as with the big book, I was testing cases all the time on these DS problems. That technique is just a lifesaver (and it even works on some PS problems!).

So what are all the NEW problem numbers? Here you go! I’ve got these organized by book and question type.

The Official Guide for GMAT® Review 2016 (aka the big OG)

Problem Solving

Key: FDP = Fractions, Decimals, & Percents; WP = Word Problems; NP = Number Properties

Data Sufficiency

Key: FDP = Fractions, Decimals, & Percents; WP = Word Problems; NP = Number Properties

The Official Guide for GMAT® Quant Review 2016 (aka the quant-only book)

Problem Solving

Key: FDP = Fractions, Decimals, & Percents; WP = Word Problems; NP = Number Properties

Data Sufficiency

Key: FDP = Fractions, Decimals, & Percents; WP = Word Problems; NP = Number Properties

What about Verbal? Next time, we’ll dive into the final summary of everything verbal and I’ll also have the problem lists for you.

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I’ve just finished trying all of the new verbal OG problems. (If you haven’t yet read my earlier installments, start here.) This installment includes my summary of All Things Verbal as well as lists of the new problems by book and question type.

Also, we’re hard at work writing new solutions to add to our GMAT Navigator program, so if you have access to Navigator, you can start to check for new solutions there in—best guess—July.

What’s new in Verbal? Now that I’ve seen everything, I’ve been able to spot some trends across all of the added and dropped questions. For example, across both The Official Guide for GMAT® Review (aka the big book) and The Official Guide for GMAT® Verbal Review (aka verbal-only or the verbal supplement), 6 science passages were added (out of 11 new passages total), while only 3 were dropped. In addition, 3 social science passages were added (compared to 5 dropped) and 2 business passages were added (compared to 2 dropped).

So, in the books at least, there’s a slight shift towards science. It’s unclear whether this signals an actual change in emphasis on the test, though; these may just be the best retired passages that they wanted to use.

For Critical Reasoning, the same total number of questions were added and dropped. The differential (added minus dropped) for Strengthen questions was +8. Further, 6 of the 22 total new Strengthen questions are fill in the blank (FitB) format, and no new FiTB’s were introduced that were not Strengthen questions.

The differential for Weaken questions was -8 and for Inference questions, it was -4. I’m not entirely sure what to make of the drop in Weaken. I’ve been hearing from students that they’ve been seeing a lot of Strengthen / Weaken on the real test and not many (CR) Inference questions. The Strengthen jump and the small Inference drop seems to go along with that, but not the larger Weaken drop. (This is why I’m always skeptical about drawing broader conclusions based on changes in the books.)

As I mentioned in my first report on Sentence Correction (part 2 of this series), it is difficult to compare categories here because one SC can (and usually does) cross multiple topics. The trends I reported before still hold after my review of the Verbal supplement: meaning and sentence structure are increasingly important, and parallelism and comparisons are just as important as they’ve always been.

Ready for the problem lists?

New verbal problem lists

The Official Guide for GMAT® Review 2016 (aka the big OG)

Reading Comprehension

Critical Reasoning

Sentence Correction

Note: we only tagged two topics per problem; many SC problems test more than two topics. Also, the order in which the topics are presented is generally whatever we happened to notice first in the original sentence or in the answers.

The Official Guide for GMAT®Verbal Review 2016 (aka the verbal-only book)

Reading Comprehension

Critical Reasoning

Sentence Correction

Note: we only tagged two topics per problem; many SC problems test more than two topics. Also, the order in which the topics are presented is random—whatever we happened to notice first!

Phew. I think that’s it… A week and several thousand words later, I think that’s all, folks! Of course, I’m sure that we’ll have plenty of things to discuss over the coming weeks as we dive more deeply into all of the fun new OG questions. But for now, I hope you’ve found this review valuable and I’m going to go take a well-earned break.

Happy studying!

Missed anything in this four-part series? Start here!

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On June 24th, GMAC (the organization that makes the GMAT®) made two announcements that change the GMAT testing game. Read on to find out what they are!

Canceled scores will NOT show on your score report In the past, we have counseled students not to worry much about canceling scores, because the vast majority of business schools are interested only in your highest scores (and this is still true). Besides, the school would have been able to see that you took a test and then canceled the scores, so they could guess that you had a “bad” test on record.

As of July 19th, if you cancel the scores from a test administration, those scores will not even show up on your record. The schools won’t have any idea that you took a GMAT that day!

As such, the conversation about when to cancel becomes trickier. I need to think about this some more, but I think I’m going to advise my students to keep any scores that are within 100 points of their goal scores.

Why? There are two possible scenarios. #1: you eventually get to your goal score. In this case, schools will see that you buckled down, studied, and really improved. Obviously, that’s a win. #2: you do not eventually reach your goal score. (Perhaps your goal score is unrealistic.) In this case, at least you still do have this other score on your record. It would be terrible to have taken the test 3 times, with scores in a certain range, but to have canceled all those scores; now you have nothing on record!

As I mentioned, GMAC has announced that this policy change will take effect on July 19th. It will apply retroactively. If you have not yet sent your scores to a particular school, then when you do finally send the scores, they will remove the canceled scores from your report.

The re-take period has been shortened to 16 days (from 31) As of July 19th, instead of waiting 31 days to re-take the exam, you’ll only have to wait 16 days. This is fantastic for someone who got sick during the exam or got really nervous and seriously messed up the timing.

Note that this could create a problem for those students who really should take longer to study for a re-take but instead try to cram it in too fast. In my experience, most people need a solid 4 to 8 weeks (if not longer!) before a re-take. Maybe 10% to 15% of the students with whom I talk could reasonably re-take in 2.5 to 3 weeks and expect to get a different score. So just be careful about this one—it’s a double-edged sword.

Thanks, GMAC! These changes are huge so I just wanted to say that. Oh, and if you want to read the full official announcement, here you go.

Happy studying!

Stacey Koprince is a Manhattan Prep instructor based in Montreal, Canada and Los Angeles, California. Stacey has been teaching the GMAT, GRE, and LSAT for more than 15 years and is one of the most well-known instructors in the industry. Stacey loves to teach and is absolutely fascinated by standardized tests. Check out Stacey’s upcoming GMAT courses here!

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Now that the new 2016 Official Guide books are out, I’d like to talk about how to use these problems to get the most out of your study. I also want to talk about what not to do, as a lot of people end up essentially wasting these great study problems (not to mention valuable time!).

What should I NOT do? Your goal is to learn from the Official Guide (OG) problems in such a way that, if you see something similar on the real test, you’ll recognize what to do on that new problem.

Keep some things in mind:

Your goal is NOT to memorize how to do the problems that you’re studying. You won’t see these exact problems on the test! Can you tell me exactly how to do a particular problem? That’s great. But I care far more whether you can tell me how you know what to do and why you want to take the steps that you take. If you can, then you’ll know how to think your way through a new problem on the real test.

Your goal is NOT to try to get everything (or even most problems) right. Sometimes, what you want to recognize fairly quickly is that you should guess immediately and move on. Other times, you want to recognize that your best strategy is to spend some time making an educated guess—and then move on. Still other times, you’ll have to be able to recognize that you initially thought you could do this one but it’s just not happening, so you’ll need to cut yourself off, guess, and move on.

This is all true not just when the clock is ticking but when you’re studying as well. Take a look at Problem Solving #152 in the 2016 Quant supplement (the smaller, quant-only book). I thought about this problem for about 15 seconds, then laughed and admitted that I will never get a problem like this one right (unless I get lucky!). My brain just doesn’t work this way. I’m not even going to bother studying this problem; if I see something like it on the real test, I’ll pick my favorite letter and move on immediately. And I won’t feel bad in the slightest. J

Most people could lift their Q and V sub-scores by 2 to 3 points just by making better decisions about what not to do while the clock is ticking.

[*] Your goal is NOT even to do all of the problems. Rather, your goal is to learn everything you can from the problems that you do study. Here’s the thing: probably 80% of what you learn will come after you have picked your answer! Your analysis of the problem itself and your own work / thought process will do the most to help you get better at thinking your way through new problems.[/list] Okay, so what SHOULD I do? You’re going to use OG problems in three different ways. The below steps apply to everything except Reading Comprehension (RC). I’ll talk about RC after.

First, as you study particular topics or question sub-types (say, quadratic equations, modifiers, or CR strengthen the argument), try 2 to 3 problems from that particular area when you’re ready to test yourself to see how well you learned the material. Start with easier to medium problems (in general, lower-numbered problems tend to be easier than higher-numbered problems). Don’t do the hard ones yet! Just make sure you’ve got the basics down.

Second, during the phase of your studies when you’re still learning all those basics (quant and grammar rules, the different CR question types, etc.), try doing small, semi-mixed (and timed!) sets of 4 to 6 questions. “Semi-mixed” means, first, that you’ll mix types (DS + PS, SC + CR + RC, or two of those three). It also means that you’ll mix up topics or question sub-types. Learning science (the science of learning!) has established very clearly that interleaving topics allows you to learn much better.

What does that mean? Interleave is the formal term for mix it up! Make a set of questions that mixes up topics you’ve been studying for the past week or so. Do not sit down and do a bunch of Rates & Work questions all in a row (this is called blocking or blocked study). You will think you’re learning well, but you won’t be learning as well as you would if you interleaved the topics.

Take a look at this video from Dr. Robert Bjork, a UCLA professor who specializes in human learning and memory. Yes, it can be a little dry, but stay till the end; the big payoff is in the last 90 seconds (it’s only 6 minutes long).

Here’s the big payoff, just in case: interleaving your study feels harder than doing blocked study, but we’re actually wrong when we think that we’re learning more via blocking. Interleaving will allow you to recall more in the long run!

Third, after you’ve learned* the general content and question type strategies, start doing longer mixed sets of about 8 to 15 questions; again, time yourself and make yourself stick to the time limit! The real test isn’t going to give you one second extra. These sets will be truly mixed; don’t include more than a couple of questions from the same sub-category and always include some questions that are randomly chosen—that is, you have no idea ahead of time what the question tests. At least 50% of the questions in the set should be randomly chosen; sometimes, do sets that are 100% random.

*Note: “learned” means you will have now gone through your study material once (say, all of your non-OG books or your classes), but you will likely have a list of things that you want to review again. Still, move to stage 3 of your OG problems. Trust me: you will learn better by studying under official conditions. Remember, on the real test, you have no idea what’s coming next and you have to figure it out each time a new question pops up on the screen!

What about RC? RC questions come in sets with a passage, of course, so here’s what you’re going to do.

Passages generally have 3 to 9 questions. For any passages with 3 to 5 questions, do that passage and all its associated questions in one batch. For any passages with 6 to 9 questions, split the questions into two batches.

The first time you do that passage, do the odd-numbered questions. Then, put that passage aside for a month or two. When you come back to it, you can do the even ones. (Note: I picked the order of odd vs. even randomly; you can reverse that if you like. But to keep your life simpler, make your choice consistent, so that two months from now, you’re not asking yourself, “Wait, did I do the odd ones or the even ones last time?”)

Is there an easier way to set up the OG problem sets? Yes! When you’re doing the shorter sets of 4 to 6, you are just going to pick them out of your book yourself; use sticky notes to mark the pages so that you can flip quickly while the clock is ticking.

You can do the same thing when you do longer sets, for the specific problems that you do choose, but note that the randomness works in your favor now. It doesn’t matter what you do for 50% (or more) of the set: pick anything! Just remember to jot down the question number.

Plus, when you want to do completely random sets, you can let the OG online program set those up for you. (Look at the cover page for chapter 1 for instructions on how to access the online program.)

Take-aways (1) Initially, use a very small number of OG problems just to test your understanding of some new question type or content area.

(2) Do most of your OGs in timed, mixed sets. Remember, interleaving your study may feel harder but you learn more in the end!

(3) Most of your learning will occur after you have finished the problem. Make sure you are thoroughly analyzing the problems you’ve already done before you start on a new set of questions; if you don’t, you’re just wasting those questions (and your study time!).

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Wouldn’t it be nice to have one common thread among all GMAT problems you’ll ever do, something you do no matter what kind of problem or content area is being tested?

I’m here to answer your prayers.

Okay, obviously, there are many things you’re going to need to learn and practice in order to get a great GMAT score—these isn’t literally just one thing to learn. But it turns out that there is one set of principles tying together everything we need to do on the GMAT.

Here it is:

You can use this on Problem Solving (PS) and Data Sufficiency (DS) problems. It’ll work on Sentence Correction (SC), Reading Comprehension (RC), and Critical Reasoning (CR). It even works for Integrated Reasoning (IR) and the essay! And I’m going to show you how.

Try this PS problem from the GMATPrep® free exams.

“*The perimeter of a certain right isosceles triangle is . What is the length of the hypotenuse of the triangle?

“(A) 8

“(B) 16

“(C)

“(D)

“(E) ”

Ready?

Glance is literally what it means. Take about 1-2 seconds to just glance and see what you have.

Is it PS or DS?

Right now, you’re rolling your eyes at me. A fellow teacher of mine did an experiment last year. She put a math question up in class for a few seconds, then pulled it off and asked the class whether the problem was PS or DS. Fewer than half of the students were able to say! People are so anxious to start reading that they don’t even take in the whole screen to see what they’ve got.

So your first task is to notice, consciously, whether you have PS or DS. This one is PS. Next:

Stories / lots of words? Numbers / formulas? Graphics?

There’s a weird number in the middle there. Don’t start reading yet! One more thing:

What are the answers like?

Hmm. Two are nice numbers and three are like the weird number in the problem. You’re not going to do anything with that knowledge yet, but do remember it.

Okay, finally, you can go ahead and Read this thing. As you read, Jot down the major information.

Note: jot means just that: write down what’s there, but do not start solving or manipulating anything yet. Just get everything on your paper.

They told me it’s a right triangle and it’s isosceles, so I drew a little picture. After a second of thought, I added the labels to remind myself that it’s isosceles. Then they gave me that equation and they asked me for the hypotenuse, which I’d labeled y.

I have not yet thought about how I’m going to solve this thing. I’m not at that stage yet! This is one of the big differences between someone who does really well on quant and someone who knows a lot of stuff but is struggling to put it together: you actually want to take your time to figure out your options before you decide how to solve.

Now, it’s time to solve, right?

Not so fast!

Now, I reflect on what I’ve got and figure out what path I want to take. If either of these first two steps / rows fail, then I know I shouldn’t even bother to go to step 3. Instead, I should just pick my favorite letter and move on.

So what have we got here? There’s a right triangle, so I actually have a second formula: the Pythagorean Theorem. I can add that to my notes, using the variables that I chose:

The answer choices make more sense now. At least one of the sides of the triangle should include since the perimeter does. And two of the sides have to be the same…hmm. I wonder if it’s as easy as saying the sides are 8, 8, and ? (I’m spilling over into step 3, Work, here.)

Oh, no, wait, that won’t work, because 8 + 8 = 16, which is smaller than . The sum of the other two sides can’t be smaller than the third side.

Back up: back to Reflect and Organize. That wasn’t a complete waste of time, because now I know the answer is not (E). I also wouldn’t guess (A) at this point, because 8 is part of the faulty calculation that I just did, so it’s probably not right. In fact, maybe 8 is too small in general. I could probably estimate to get rid of some of the other answers. Something to keep in mind if I can’t come up with a better plan.

I could also work backwards, just trying the answers in the problem. That’d be pretty easy for (A) and (B), but the other two remaining answers are more annoying.

Oh, back to my original idea: I first tried to split the 16 into two parts (8 and 8), but they weren’t big enough to be the legs. What if I split into two parts? Let’s do some more Work.

In this case, the two legs would be and the hypotenuse would be 16. Does that fit the Pythagorean theorem?

Bingo! This math works, so the hypotenuse equals 16.

The correct answer is (B).

Right now, you may be thinking, “Yeah, that’s okay for you; you do really well on this test. But I can’t take all that time to Reflect and Organize before I start Working!”

I know you feel that way…but you’re wrong! You’re nervous that you’ll need more time to solve, because you’re used to diving in and trying to solve without a clear plan and that approach, naturally, takes a lot of time. If you can actually come up with a clear plan, your solution process will be a lot faster—I promise.

What if you can’t come up with a clear plan? Then your best bet is to bail on this question. Don’t start writing down random numbers / formulas and seeing where they take you, using up precious time and mental energy. Get out of the problem entirely!

Let’s take a look at some of the other paths that I rejected.

Working Backwards You can work backwards when the answer choices represent a discrete number or variable in the problem and those answers are relatively “nice” numbers. In this case, (A) and (B) are very nice. The other three aren’t quite as nice, but they may not be terrible.

We generally recommend starting with answer (B) or (D). Answer (B) is easier, so start there.

Now, we got lucky, because the first one we tried worked. What if we’d tried answer (D) first instead?

The math actually isn’t that horrible, after all, even though the starting number is annoying. I still like the first way I did it better, but if I hadn’t thought of that, then this is a good alternative approach.

Estimation I also noted earlier that I might be able to eliminate some answers via estimation.

If the hypotenuse is 8, for example, then the two legs have to be smaller than 8, so the total perimeter has to be less than 24. is definitely greater than 24, so 8 can’t be the hypotenuse.

What about ? The square root of 2 equals approximately 1.4. Call it 1.5, since we’re estimating. (4)(1.5) = 6, which is even smaller than 8. Answer (C) can’t be correct either!

Let’s try . That’s about 12, so the two legs would have to be smaller, and the perimeter would have to be less than 36.

Hmm. is about 16 + (16)(1.5) = 16 + 24 = 40. It can’t be answer (D) either. We’re down to 2 answer choices, just by estimating! Let’s keep going.

If the hypotenuse is 16, then the perimeter has to be less than 48. That works with the 40 figure. And if the hypotenuse is , then the numbers could also fit.

We’re down to two answers just by estimating, and if you’d already figured out, as we did at the beginning, that (E) couldn’t be right, then you’d know the answer has to be (B)!

Keep an eye out for this series; every week, I’ll be doing a new problem type using the overall GRW approach. (GRW = the first letters of each of the three lines. Maybe you can help me come up with a better name for this…)

Key Takeaways for Every Problem You Will Ever Do: (1) First, you have to understand what’s in front of you. Glance at the problem to pick up any clues you can about what it is, where the complexity is, and what kinds of strategies might be available to you. As you Read, Jot down the given information—but don’t try to solve yet!

(2) Next, Reflect on what you’ve been given and Organize your thoughts and your scrap paper. Notice how much thinking I did before I went ahead and solved the thing? I came up with three different approaches and then picked the one that seemed the best to me. And here’s the best part: this valuable investment of time will help you to pick the best path when you can do so and it will help you to guess and move on when that’s the best call to make.

(3) Finally, you get to do the Work to solve this thing, assuming that you actually passed the first two steps: you understand the problem and you have a plan to solve. If not, then your best move is to make an educated guess when possible (estimate, for example) or just pick your favorite letter and move on.

* GMATPrep questions courtesy of the Graduate Management Admissions Council. Usage of this question does not imply endorsement by GMAC.

Stacey Koprince is a Manhattan Prep instructor based in Montreal, Canada and Los Angeles, California. Stacey has been teaching the GMAT, GRE, and LSAT for more than 15 years and is one of the most well-known instructors in the industry. Stacey loves to teach and is absolutely fascinated by standardized tests. Check out Stacey’s upcoming GMAT courses here!

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Try this Data Sufficiency (DS) problem from the free GMATPrep® exams. (Note: if you have not yet taken your two free GMATPrep exams, you may want to wait until you’ve done so before you read further. Also, if you have not yet studied DS enough to know what the five answer choices are, bookmark this article and come back to it after you have memorized the DS answer choices.)

“*Is x less than 20?

“(1) The sum of x and y is less than 20.

“(2) y is less than 20″

Ready?

Here’s our framework for working through a GMAT problem:

Glance: It’s a DS problem. Words—I’ll have to do a little translating. Doesn’t seem to be a big story, though.

Read: It’s a yes/no question, so I don’t necessarily have to find the exact value of x.

Jot:

Is x < 20?

Reflect: They haven’t actually told me anything about x. The value could be anything: negative, 0, a fraction.

Jot some more and Organize. The two statements are pretty easy, so I chose to translate both at once, before starting to work on them:

Note: Although statement (2) is arguably easier, statement (1) isn’t really hard. My default is to start with statement (1) unless it looks ugly or annoying, so I’m starting with statement (1).

Reflect again, then Work. What should I do with statement (1)? I can test cases:

Look what I did there. The first case that I tested did give me a Yes answer. But then I didn’t just pick any random number to try for my second case. I thought, “Hey, what could give me the opposite answer? I want to find a No, if possible!”

(By the way, that “val?” column is short for “valid?” It’s crucial to make sure that you choose numbers that make the statement valid. Otherwise, discard that case!)

Okay, so statement (1) is not sufficient (NS); eliminate answers (A) and (D). What about statement (2)? It doesn’t even mention x, so it’s not sufficient either. Eliminate answer (B). Put the two statements together.

Check it out! The first two cases for statement (1) still work even when you add statement (2) to the mix. Even together, the two statements are not sufficient to answer the question.

The correct answer is (E).

Try this one (also from GMATPrep) and we’ll talk about it next time:

“*If 0 < r < 1 < s < 2, which of the following must be less than 1?

“I.

“II. rs

“III. s – r

“(A) I only

“(B) II only

“(C) III only

“(D) I and II

“(E) I and III”

Key Takeaways for Getting to No: (1) Your job is to be a skeptical scientist. What better way to confirm your theory than to try to disprove it as rigorously as you can? If you can find a valid case that gives a No answer, as well as a case that gives a Yes answer, then you’re done: this statement is not sufficient to answer the question.

(2) If you are actively trying to disprove and you can’t, then the chances are pretty good that this statement is actually sufficient. Yes, it might be the case that you have just not found the right number to test yet. But if you are actively trying to disprove, then your brain will be thinking about the “weird” numbers that might make a difference—so you can feel pretty confident that you’ve probably got it.

* GMATPrep® questions courtesy of the Graduate Management Admissions Council. Usage of this question does not imply endorsement by GMAC.

Stacey Koprince is a Manhattan Prep instructor based in Montreal, Canada and Los Angeles, California. Stacey has been teaching the GMAT, GRE, and LSAT for more than 15 years and is one of the most well-known instructors in the industry. Stacey loves to teach and is absolutely fascinated by standardized tests. Check out Stacey’s upcoming GMAT courses here!

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For the past several months, we have engaged Dr. Lawrence Rudner, former Chief Psychometrician of the Graduate Management Admissions Council (GMAC, the makers of the GMAT®), to review our practice tests. Dr. Rudner is one of the world’s leading experts in item response theory, the testing principle on which the GMAT is based. He is the definitive authority on the GMAT examination.

And here’s what he has to say about Manhattan Prep’s practice exams:

“I conducted an extensive examination of student data for all of the Manhattan Prep test questions and I was very impressed. I can attest to the fact that very high percentages of Quant and Verbal items have excellent psychometric properties. I can further attest that Manhattan Prep’s GMAT practice exams do an excellent job of predicting a student’s score on the actual GMAT examination. Manhattan Prep’s GMAT practice exams can help you accurately gauge when you’re ready to achieve your goal score on the real test.” – Lawrence M. Rudner, PhD, MBA

In short, our tests do “an excellent job of predicting” your score on the real GMAT. That’s great news!

I am particularly excited about the fact that our CATs were so strong that Dr. Rudner offered his endorsement without requiring us to change a single thing. Going into the review, we had thought that we would be given a required list of changes before he could give his seal of approval.

I do have to add a caveat: nothing is perfect and not everyone scores on the real test exactly what they scored on our test (or any practice test). No standardized test is that precise, including the real GMAT. There are also other factors that can negatively affect certain students, such as anxiety (you know your practice tests don’t really count) or mental fatigue (don’t study for 6 hours the day before the real exam!).

Caveat over. In general, you can trust our exams to help you know when you’re ready to get in there and take the real thing. I already felt that way before, but now I can say it with conviction, because Dr. Rudner has confirmed the accuracy of our exams.

I have to give a shout-out to all of our instructors who have worked so diligently on our exams over the years—you know who you are. We literally would not be having this conversation right now if not for your hard work and dedication to making our materials the best. Thank you for your love of teaching and your complete fascination with the GMAT. I’m proud to call you colleagues and friends.

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Not sure what you should be aiming for on the GMAT? Manhattan Prep instructor & GMAT expert Johnathan Schneider breaks down what a good GMAT score is and what it means for you.

Want to know more about your score? Take a free GMAT practice test now. And be sure to check back every Tuesday for a new video in our GMAT 101 series, detailing some of the most frequently asked questions about the GMAT.

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Last time, we talked about how crucial it is to develop the instinct to go for the “No” when taking the GMAT. If you haven’t read the first installment, do so right now, then come back here to learn more.

I left you with this GMATPrep® problem from the free exams.

“*If 0 <r< 1 <s< 2, which of the following must be less than 1?

“I.

“II. rs

“III. s – r

“(A) I only

“(B) II only

“(C) III only

“(D) I and II

“(E) I and III”

Let’s talk about it now!

What did you think when you first Glanced at this thing? I thought, “Ugh, roman numerals.” These questions annoy me because they often take longer to do. In fact, unless I can spot some kind of shortcut, I may bail and move on. I’m not interested in doing the work of 3 problems for the price of 1!

When I Read this one, though, I realized it wasn’t too terrible. I Jotted this down while I read:

0 <r< 1 <s< 2 MUST be < 1?

And then I Reflected. First, I glanced at the statements and saw that they all contain both r and s. I also glanced down at the answers and thought, “Hmm, I bet roman numeral I works; it’s in three of the answer choices.”

Then, I looked back at the stuff I jotted down and thought about what it tells me. The value of r is between 0 and 1; it’s a fraction. The value of s is between 1 and 2. All right, that’s also technically a fraction or decimal, but it’s a very different category than r, which is a fraction between 0 and 1. Fractions between 0 and 1 can do funny things to certain math operations.

They want to know what must be less than 1, so that would either be another fraction between 0 and 1, the number 0, or something negative.

I think I’ve got my thoughts all Organized. Time to Work on this thing!

“I. “

Time to test cases. What if r = and s = ? Then:

Yes, that’s less than 1. Can I get a no? In order to do that, I’d have to get 1 or something greater than 1.

I can’t get 1 because r and s don’t equal each other. What about something greater than 1?

Think it through. Turns out, that’s impossible! The numerator is the starting point. It’s between 0 and 1. Then, divide by the denominator. That’s greater than 1. Dividing by a number greater than 1 will always have the effect of making the numerator smaller. If the numerator is already smaller than 1, then the final number can’t be larger than 1.

Done! The first roman numeral must be less than 1. Eliminate answers (B) and (C). (Note: if you had to guess on this one, guess that it works, since roman numeral I appears in three of the five answer choices.)

In fact, glancing at those answers before you start to solve may help you to manage your time. You might be annoyed by the amount of work necessary to solve this one and decide that you’ll only try roman numeral I, since it shows up in three of the answers. Then, when you’ve eliminated either two or three of the answers after evaluating just one statement, you might guess and move on.

“II. rs”

Test cases again! Remember that r still has to be between 0 and 1 and s still has to be between 1 and 2.

Case 1: r = 1/2 and s = 3/2. The product is 3/4, which is less than 1.

Can you find a no? Try before you keep reading.

In this case, a variation on testing cases might be valuable: test extremes. The upper limit for r is something just a little bit less than 1. Likewise, the upper limit fors is something just a little bit less than 2. What would happen if r and s actually equaled 1 and 2, respectively?

Then, the product would be 2. So the product of a number just a little bit less than 1 and another number just a little bit less than 2 should be a little less than 2—but greater than 1. This statement, then, does not have to be less than 1.

You can also test numbers to prove this. Make both numbers as big as you can while still making the math not-too-terrible to do. If s = 1.8 and r = 0.9, then think of the math as taking 90% of 1.8. That’s greater than 1, even if you don’t do the exact math to figure out what that product is.

Eliminate answer (D).

“III. s – r”

Last one! Okay, remind yourself again: s is between 1 and 2 and r is between 0 and 1. (Careful. Note that the order of the variables is reversed now.)

Case 1: If s = 3/2 and r = 1/2, then the difference is 1. Hey, for the first time, the first case is not less than 1! This statement also doesn’t qualify, so eliminate answer (E).

The correct answer is (A).

Key Takeaways for Getting to No: (1) You can use the Getting to No technique on some problem solving (PS) questions, too, not just data sufficiency. When you see PS questions that ask what must or could be true (or cannot be true), don’t just go for the Yes! Think about how to Get to No. (Remember the Skeptical Scientist takeaway from part 1 of this series).

(2) If you are actively trying to Get to No but can’t, then the chances are pretty good that this statement actually must be less than 1 (or whatever the problem asks you to find). In your quest to find that No, you may even be able to prove why you can’t get there, as we did for roman numeral I in the problem above.

* GMATPrep® questions courtesy of the Graduate Management Admissions Council. Usage of this question does not imply endorsement by GMAC.

Stacey Koprince is a Manhattan Prep instructor based in Montreal, Canada and Los Angeles, California. Stacey has been teaching the GMAT, GRE, and LSAT for more than 15 years and is one of the most well-known instructors in the industry. Stacey loves to teach and is absolutely fascinated by standardized tests. Check out Stacey’s upcoming GMAT courses here

ForumBlogs - GMAT Club’s latest feature blends timely Blog entries with forum discussions. Now GMAT Club Forums incorporate all relevant information from Student, Admissions blogs, Twitter, and other sources in one place. You no longer have to check and follow dozens of blogs, just subscribe to the relevant topics and forums on GMAT club or follow the posters and you will get email notifications when something new is posted. Add your blog to the list! and be featured to over 300,000 unique monthly visitors

ForumBlogs - GMAT Club’s latest feature blends timely Blog entries with forum discussions. Now GMAT Club Forums incorporate all relevant information from Student, Admissions blogs, Twitter, and other sources in one place. You no longer have to check and follow dozens of blogs, just subscribe to the relevant topics and forums on GMAT club or follow the posters and you will get email notifications when something new is posted. Add your blog to the list! and be featured to over 300,000 unique monthly visitors

How are you with story problems? Most math concepts can be presented in story form on the test and the GMAT test writers do like to get wordy with us. You’ve got a double task: you have to translate the words into math and then you still have to do the math! How can we get through these as efficiently as possible?

Try the GMATPrep® problem below and then we’ll talk about it. Give yourself about 2 minutes. Go!

* “On a certain sight-seeing tour, the ratio of the number of women to the number of children was 5 to 2. What was the number of men on the sight-seeing tour?”

“(1) On the sight-seeing tour, the ratio of the number of children to the number of men was 5 to 11.

“(2) The number of women on the sight-seeing tour was less than 30.”

Got your answer? (If you’re wondering where / what the answer choices are, click here to learn about Data Sufficiency before proceeding with this problem.)

All right, so W : C is 5 : 2 and they want to know…oh, that’s interesting. They’re asking for the number ofmen. In other words, there are three groups here, not just two.

After I write that down, I glance back up at the screen to make sure I’ve got everything transcribed correctly. Okay, not much else I can do here. Moving on to statement (1).

“(1) On the sight-seeing tour, the ratio of the number of children to the number of men was 5 to 11.”

Hmm. They’re giving me another ratio.

Even as I’m jotting this info down, I’m skeptical. Why?

There are no real numbers here. They didn’t ask for the ratio of men to anything. They just want the actual number for M.

Statement (1) is not sufficient. Cross off choices (A) and (D). Next up, statement (2).

“(2) The number of women on the sight-seeing tour was less than 30.”

Yes! Now they’re giving me a real number! So now I can solve.

Oh, wait. Careful: the question stem doesn’t contain any info about the men. This is why I organize my scrap paper in the way that I’m showing you: I’ve “segregated” the various pieces of info so that I can catch myself when I might try to use certain pieces of data at the wrong time. Right now, I have to completely ignore statement (1); it doesn’t exist. I can figure out some possibilities for the number of women but nothing about the number of men.

Okay, statement (2) doesn’t work either; cross off answer (B).

So now we get to use everything. Does that help?

Yes, it does! First, the two different ratios can be combined into one big ratio. To do that, the “like” portions of the two ratios have to be made the same:

That ratio can’t be simplified further, because the 25 is not even but the 10 and 22 are.

Next, there are fewer than 30 women. The women have to represent 25 in the ratio; in other words, the number of women must be a multiple of 25. There’s only one possible multiple of 25 that is also less than 30: 25 itself! There must be exactly 25 women, 10 children, and 22 men. Done!

The correct answer is (C).

One big trap on this problem is assuming that the inequality given for statement (2) won’t be enough. The (faulty) thinking goes: the problem asks for a specific value, and a range (less than 30) isn’t going to be enough to get to one specific value.

Turns out, in this case, it is! It can be tricky on DS to know when to stop the math; you don’t want to have to solve every problem completely or you’ll take way too much time. In this case, the clues for me were:

(1) “Less than 30” isn’t all that many possible values

(2) The two “like” parts of the ratio (children and children) are different enough to start (5 and 2) that the final ratio numbers might end up being quite large…so maybe “less than 30” will be good enough after all

Okay, want to try another? Try this GMATPrep® problem from the free question set, then join me next time to discuss the solution.

“A certain wooded lot contains 56 oak trees. How many pine trees does the lot contain?

“(1) The ratio of the number of oak trees to the number of pine trees in the lot is 8 to 5.

“(2) If the number of oak trees were increased by 4 and the number of pine trees remained unchanged, the ratio of the number of oak trees to the number of pine trees in the lot would be 12 to 7.”

Key Takeaways: Work methodically and don’t stop too soon! (1) On story problems, half the battle is translating accurately. It’s easy to make careless mistakes (such as reversing two categories), and of course, sometimes the translation is just tricky. After you’ve translated the story, double-check your notes against the screen to make sure everything’s where it should be.

(2) Two ratios can be combined into one, as long as they overlap somewhere. The “like” category needs to be made the same number for both ratios; then you can combine them into one big ratio.

(3) Don’t stop too soon on DS! When they give you a range of possible values, don’t automatically assume it isn’t enough. See whether there are other constraints in the problem that might narrow down all of the possibilities to just one answer. If so, you’ve got sufficiency!

* GMATPrep® questions courtesy of the Graduate Management Admissions Council. Usage of this question does not imply endorsement by GMAC.

Stacey Koprince is a Manhattan Prep instructor based in Montreal, Canada and Los Angeles, California. Stacey has been teaching the GMAT, GRE, and LSAT for more than 15 years and is one of the most well-known instructors in the industry. Stacey loves to teach and is absolutely fascinated by standardized tests. Check out Stacey’s upcoming GMAT courses here!

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Welcome to part 3 of our series on how to answer every single GMAT problem you’ll ever see. If you haven’t already read the earlier installments, start with part 1 and work your way back to me.

This time, we’re going to test out the process with a GMATPrep® Sentence Correction question from the free exams. Here you go:

“In archaeology, there must be a balance between explanation of the value and workings of archaeology, revealing the mysteries of past and present cultures, and to promote respect for archaeological sites.

“(A) between explanation of the value and workings of archaeology, revealing the mysteries of past and present cultures, and to promote

“(B) among explaining the value and workings of archaeology, revealing the mysteries of past and present cultures, and promoting

“(C) between explaining the value and workings of archaeology, the revealing of the mysteries of past and present cultures, and when promoting

“(D) among explaining the value and workings of archaeology, the revelation of the mysteries of past and present cultures, and to promote

“(E) between explaining archaeology’s value and workings, in the revealing of the mysteries of past and present cultures, and in promoting”

Got your answer? Let’s do this!

First, Glance at the problem. What does that even mean for SC? There’s so much text!

Don’t read the sentence yet. Here’s where to glance:

Start with the word before the underline and the first underlined word

Then glance down the first word or two of each answer choice

That’s it! Now what do you do with that information?

Some words are markers all by themselves: if you see the word and, you know something is going on with parallelism.

Other clues make themselves known when you compare differences in the answers, and there’s always one difference at the beginning of each answer choice. You may not always know what the difference signifies, but if you train well, you can learn to spot clues on a First Glance something like 70% to 80% of the time.

Why do this before you even read the sentence? On SC, it’s often hard to find a starting point, since each sentence could be testing anything and just what it’s testing is not always obvious. Sometimes you read a sentence and just shrug, not sure what’s going on. If your first glance can provide you with a valuable clue as to what is being tested (or what might be tested), then you can read that sentence with a point of view: you’re actively looking for a particular issue. That will more quickly point you towards at least one of the issues going on in the sentence!

So go back up and glance at that problem right now. What do you notice?

balance between

The word between is part of the idiom between X and Y. Less commonly, you may see a split in the answers between between and among. (See what I just did there? ) Glance down the beginning of the answers … yep, this one is testing between vs. among. I’d jot down between/among on my scrap paper. (Actually, I’d use shorthand and write bet/am. I know what this means because I’ve used this abbreviation before.)

Excellent! I’m jumping to Reflect because my Glance actually gave me something to think about. Do you know how those two words are used? Between is used when talking about exactly two things; among is used for three or more things. Now I know what to think about when I go back up for my next step: Read.

Okay, the sentence has a list of three: explanation, revealing, and to promote. I know immediately thatbetween is wrong; I need to choose an answer that uses among. Also, this construction requires parallelism … and that list does not look very parallel. I’ll come back to that in a minute.

Work! Cross off answers (A), (C), and (E). That was nice—only two to go. Now let’s go back to check out that parallelism issue.

“(B) among explaining the value and workings of archaeology, revealing the mysteries of past and present cultures, and promoting

“(D) among explaining the value and workings of archaeology, the revelation of the mysteries of past and present cultures, and to promote”

Answer (B)’s list items are explaining, revealing, and promoting. Looking nicely parallel!

Answer (D)’s list items are explaining, the revelation, and to promote. A participle, a noun, and an infinitive verb: not parallel! (An –ing word can be a noun or a verb, but a noun and an infinitive verb cannot be parallel to one another.)

The correct answer is (B). And I barely had to read anything among those five long answer choices. (See what I did again there? )

You may have noticed that, on SC, we have to back and forth between the steps of the process a lot. This is one of the annoying parts of SC. Every time you get a clue, you figure out what it means (Reflect & Organize!) and cross off some answers (Work!), but then you typically have to go back and start all over again. One clue typically won’t allow you to cross off all four wrong answers (though this does happen sometimes).

In fact, we incorporate these ideas into our 4-step SC Process. (Yes, I know that the article I just linked technically lists 5 steps … but the fifth step is really just repeat.)

Try the process out again on the GMATPrep® problem below and I’ll give you the answer in our next installment.

“The new image of Stone Age people as systematic hunters of large animals, rather than merely scavenging for meat, have emerged from the examination of tools found in Germany, including three wooden spears that archaeologists believe to be about 400,000 years old.

“(A) merely scavenging for meat, have emerged from the examination of tools found in Germany, including

“(B) as merely scavenging for meat, have emerged from examining tools found in Germany, which include

“(C) as mere meat scavengers, has emerged from examining tools found in Germany that includes

“(D) mere scavengers of meat, has emerged from the examination of tools found in Germany, which includes

“(E) mere scavengers of meat, has emerged from the examination of tools found in Germany, including”

Key Takeaways for Every Problem You Will Ever Do: (1) First, you want to see whether a quick look can give you an early idea of one topic the sentence may be testing. Glance at the word right before the underline and at the first word of the underline: any clue markers there? Next, compare the first word or two of each answer choice: do the differences signal any particular issues?

(2) If so, Reflect briefly on what is or might be happening, then Read the original sentence, Jotting down any important markers or reminders as you go. When you’ve found a starting point, Reflect again to decide what to do with this piece of information.

(3) When you know you’ve got an error, cross off that answer choice and any others that repeat the same error. As you do this, keep an eye out for clues that can help you find the next starting point, as in this problem when the first clue (between / among) led me to the second issue (parallelism). After several rounds, you’ll either be down to one answer or you’ll realize that this one is too hard and you’ll guess from among the remaining choices.

* GMATPrep® questions courtesy of the Graduate Management Admissions Council. Usage of this question does not imply endorsement by GMAC.

Stacey Koprince is a Manhattan Prep instructor based in Montreal, Canada and Los Angeles, California. Stacey has been teaching the GMAT, GRE, and LSAT for more than 15 years and is one of the most well-known instructors in the industry. Stacey loves to teach and is absolutely fascinated by standardized tests. Check out Stacey’s upcoming GMAT courses here!

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Can you learn everything you need to know in order to ace the GMAT on your own?

Yes, but there are varying degrees of study with varying levels of difficulty. Watch this quick video to learn more about your options. Ready to get started? Check out our free GMAT prep resources.

Want more useful GMAT basics? Check out the rest of the GMAT 101 series.

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Recently, we took a look at a story problem dealing with ratios, and I finished up by giving you a second problem to test your skills. How did you do?

If you haven’t already, try the GMATPrep® problem below and then we’ll talk about it. Give yourself about 2 minutes. Go!

* “A certain wooded lot contains 56 oak trees. How many pine trees does the lot contain?

“(1) The ratio of the number of oak trees to the number of pine trees in the lot is 8 to 5.

“(2) If the number of oak trees were increased by 4 and the number of pine trees remained unchanged, the ratio of the number of oak trees to the number of pine trees in the lot would be 12 to 7.”

Ready? (If you’re wondering where / what the answer choices are, click here to learn about Data Sufficiencybefore proceeding with this problem.)

The question stem doesn’t give a lot of info. There are 56 oak trees and we need to find the number of pine trees.

Statement (1) is shorter, so let’s start there.

“(1) The ratio of the number of oak trees to the number of pine trees in the lot is 8 to 5.”

Okay, a ratio. Is that useful?

Aside: Wondering why I wrote my o’s like that? If I didn’t add the slash, I might mix them up with zeros. I also put slashes through z’s (they look like my 2’s) and s’s (they look like my 5’s).

Okay, so if you have a ratio and you also have the real number for any one portion of that ratio, then you can figure out everything in that ratio.

In this case, if there are 56 oak trees in a ratio of 8 oaks to 5 pines, then the “unknown multiplier” is 56/8 = 7. There are (8)(7) = 56 oaks and (5)(7) = 35 pines.

This is data sufficiency, so you don’t actually need to calculate that; you just need to be able to tell that youcan calculate it. Statement (1) is sufficient. Cross off choices (B), (C), and (E).

Next up, the slightly more annoying (by length) statement (2):

“(2) If the number of oak trees were increased by 4 and the number of pine trees remained unchanged, the ratio of the number of oak trees to the number of pine trees in the lot would be 12 to 7.”

Hmm. More complicated. Let’s see: there are 56 oak trees, so if they are increased by 4, then there would be 60 oak trees. We can still use p to represent the pines; that number doesn’t change.

Oh, check that out. I’m glad I wrote that out so that I could see what was going on. Turns out, we have the same info that statement (1) gave us: a real number for the oak trees and a ratio. That allows you to calculate the “new” number of pines, which is the same as the “old” number.

Okay, statement (2) also works, so the correct answer is (D).

By the way, just to practice your computation skills, how many pines are there in the second scenario? (You don’t actually have to solve this on data sufficiency, of course.)

If there are 60 oaks, then the unknown multiplier is 60/12 = 5. Therefore, there are (7)(5) = 35 pine trees.

Key Takeaways: Write everything out! (1) It can be tempting to eyeball some information and go with a gut feel, but this can sometimes get you into trouble. I’ve seen people look at statement (2) and think that it’s not sufficient without actually writing out the work. They’ll sometimes think that you can calculate the new number but not the old one, forgetting that the number of pine trees doesn’t change.

(2) Know the “unknown multiplier” rule: if you have the ratio and one real number for anything in that ratio, then you can calculate the real numbers for all parts of that ratio.

* GMATPrep® questions courtesy of the Graduate Management Admissions Council. Usage of this question does not imply endorsement by GMAC.

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The new Official Guide books are here! Aren’t you excited?!?

Okay, I realize that most people probably aren’t as excited as I am. But there are still some interesting and useful things to know about these new books as you get ready to take the GMAT. So let’s talk about it!

In this installment, I’ll discuss additions and changes to quant sections for The Official Guide for GMATÒ Review 2016, aka the OG or the big book. Keep an eye out for later installments, in which I’ll discuss the Verbal section of the big book, as well as the Quantitative Review and Verbal Review books. I’ll also be providing you with a list of the new questions, in case you decide to study from both the 2015 and 2016 editions.

If you haven’t already bought your official guide books, then do buy these latest editions—sure you might be able to get a discount on the 2015 editions, but since you have to spend money anyway, you might as well work from the latest and greatest.

If you have already bought the older editions and are debating whether to buy the new ones, too, then you’ve got a decision to make. On the one hand, there are a lot of great new questions in the 2016 editions. On the other, the 2015 edition already has a ton of problems; you may not need even more. If it were me, I’d wait until I’d used up the ones in the materials I already have. If I still felt that I needed more beyond that, then I’d consider getting one or more of the new books.

What’s new in OG 2016? Approximately 25% of the questions are brand new, and there are some beauties in the mix. As I worked through the problems, I marveled anew at the skill with which the test writers can produce what I call elegant problems. On the quant side, I saw example after example in which the problem can be solved with little to no computation as long as you can decode and understand the fundamental concept underlying the problem—that’s the real test-taking skill!

Rich D’Amato, spokesperson for GMAT, confirmed that a decent number of the new questions were produced relatively recently; that is, you’ll be seeing questions that were on the real exam not too long ago. (The older questions are still great study questions, too; the GMAT is a standardized test so, by definition, the test makers can’t change things too drastically or rapidly. There can be some mild trends over time, though. For example, the test makers may decide that certain idioms should be retired from or introduced for Sentence Correction problems.)

The opening chapters of the book describe how the GMAT works and how to study for the test; these sections have not changed. Nor has the Math Review (chapter 4). This is no surprise—again, the GMAT is a standardized test and, as such, it remains very consistent over time. The Diagnostic test in chapter 3 also has not changed.

What’s new in Quant? Overall, I noticed multiple new problems that crossed two or (occasionally) even three content areas. For instance, #18 is a geometry question that also crosses into percents, as does overlapping sets Problem #91. I chose those two examples on purpose so that I could also point this out: fractions and percents, in particular, are really good concepts to cross over into any other content area, so make sure you have a very solid foundation in both fractions and percents.

I also noticed a few visual questions—a couple of 3-D geometry and some coordinate plane problems that were made much harder by my general tendency to struggle with this kind of visual stuff. If you’re like me, beware; you may decide ahead of time that you want to bail immediately on 3-D or other problems that have a heavy visual component.

Problem Solving

Of the 230 questions in the Problem Solving (PS) section, 58 of them are new. (Disclaimer: I hope I counted correctly for all of these sections, but I’ve been going through about 1,500 questions and hundreds of pages quickly in order to get this review out to you right away. So please forgive me if I miscounted anything! I’ll correct any errors as soon as I find out about them.)

I noticed a number of what I’ll call “practical” questions: the question, usually a story problem, reads like something you might be asked to figure out in the real world. Problem #11, for example, asks you to figure out the minimum number of questionnaires you’d need to mail in order to achieve a certain desired number of responses. (The problem includes an assumed response rate.)

Note: I can’t actually reproduce the text of the question for copyright reasons, but I’m citing the problem number so that you can look it up if you do decide to buy the book.

Problem #39 can literally be counted out on your fingers—as long as you understand what you’re being asked to do. Be careful with definitions!

I also saw several problems that seriously disguised what the question was getting at. I don’t want to spoil you for the questions—better if you can figure it out for yourself!—but take a close look at #68 and #83. On the surface, these would be classified as algebra. But at least one can be done more easily using a different set of concepts. (I’ll tell you at the end of this article. But don’t look until you’ve tried to figure it out yourself!)

I used smart numbers to solve a number of the problems and I also worked backwards multiple times. In other words, these strategies are just as important as they always were. I did notice one question (#99) on which we could use smart numbers but the form of the answers indicated that it’d almost certainly be easier to do algebra. Look at the problem; you’ll see what I mean!

Finally, let’s talk about those elegant questions. If you can understand the concepts underlying #97, then you barely need to calculate anything at all—even though it looks as though you’re going to need to do some annoying algebra to answer the problem. Likewise, #107 has a huge disguise that, once uncovered, allows you to answer in two seconds without calculating anything at all. (Again, I’ll tell you what this is at the end of this article.)

Data Sufficiency

Of the 174 Data Sufficiency (DS) problems, 45 are new to this edition of the OG.

Continuing on the theme from PS, I was really struck by the number of new story problems for which translation is the whole key. If you translate carefully and accurately, then you don’t need to do anything more to solve. For example, #38 looks particularly nasty. Translate that thing very carefully, though, and you won’t have to do any messy calculations to answer. Problem #83 is another example; the story is pretty confusing, but if you can lay out the parts carefully and clearly, then the rest of the problem is more about logic than math.

Next, I used testing cases numerous times; as with PS, the standard test-taking strategies are still in full evidence on DS. I also noticed that, as before, it’s crucial to make sure you know what you were asked to find. This is true on PS too, of course, but DS tends to set more traps around solving for the wrong thing. Check out #39. You can’t find t by itself, but you can find t2, and that’s good enough to solve.

So what were all those cool disguises and tricks you mentioned? Here you go. Again, do not read this until you have worked on these problems yourself! If you can figure out what’s going on yourself, the lesson will stick much better in the end. J

PS #68 and #83. These two problems share a consecutive integer disguise. The givens can be read to mean consecutive integers (the second one has to be rearranged to do so) and, since in each case the two terms multiply to an integer, that tells you that you’re dealing with the factors of that integer. For instance, in #68, the factors of 24 are (1, 24), (2, 12), (3, 8), and (4, 6). BUT note that the problem does not actually mention factors or specify positive numbers, so you also have to take into account that the pairs could be negative.

Next, you know that they have to be consecutive odds or consecutive evens, so the only two pairs that work are (4, 6) and (-4, -6). From there, you can figure out the answer. Problem #83 has a similar disguise, although it can also be solved via quadratic equations.

PS #97. The question asks you to maximize the depth, N(t). The -20(t – 5)2 term has that negative sign out front, so it could reduce the depth, so you need to minimize the negative value. How? Make the (t – 5) term equal to zero!

PS #107. I love this one. It’s a weighted average question in disguise. The formula x + y = 1 signifies that the two weightings add up to 100%: x + y = 100%, where x and y are the two weightings. The formula 100x + 200y signifies the weightings that you’re applying to each of the two endpoints, 100 and 200. The weighted average must be somewhere between the two starting numbers / endpoints, so only two of the roman numerals can work.

DS #38. The question tells you to set (1/12 + kv2) equal to 5/12. Then it asks you for v. If you know k, then you can find v. So the real question is whether the statement allows you to find k. Statement (1) obviously does, and statement (2) also does, because it gives you another equation: (1/12) + k(30)2 = 1/6.

DS #83. There are x processors. Each processor can process up to y calls. Think about what this means—maybe even draw a picture. Note that x has to be at least 1 and y has to be at least 1. If you have x = 1 processor that can process y = 500 calls, then sure, you can process 500 calls at once. If you have x = 10 processors that can process y = 10 calls each, then nope, you can’t process 500 calls at once.

So you need to know something about x and y in order to answer. It looks, then, like statements (1) and (2) can’t work alone, since each talks about only one variable. But don’t forget the constraint that each has to be at least 1!! If you have x = 600 processors, then you can definitely process 500 calls, since each processor has to be able to process at least one call.

What about Verbal? And the other books? Next time, we’ll dive into the verbal sections of the Big OG. Then, we’ll discuss the quant and verbal supplements, and finally, I’ll provide you with lists of the new questions in each book and also the new question numbers for the old questions that remain in the book from the last edition.

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Welcome to the fourth installment of our series: how to tackle every problem on the GMAT. If you’re joining in the middle, go back and learn about the set of principles that tie together everything we need to do on the GMAT. Then work your way back to this installment.

Here’s our framework again:

I finished off part 3 with the following GMATPrep® problem from the free exams. Let’s use the SC process to answer it now.

“The new image of Stone Age people as systematic hunters of large animals, rather than merely scavenging for meat, have emerged from the examination of tools found in Germany, including three wooden spears that archaeologists believe to be about 400,000 years old.

“(A) merely scavenging for meat, have emerged from the examination of tools found in Germany, including

“(B) as merely scavenging for meat, have emerged from examining tools found in Germany, which include

“(C) as mere meat scavengers, has emerged from examining tools found in Germany that includes

“(D) mere scavengers of meat, has emerged from the examination of tools found in Germany, which includes

“(E) mere scavengers of meat, has emerged from the examination of tools found in Germany, including”

Ready?

Glance: What have we got?

than merely

I’m wondering what the than is a part of, so my eye goes a little further back:

rather than merely

Ooh—comparison! What about the beginning of the answers?

“(A) merely scavenging

“(B) as merely scavenging

“(C) as mere meat scavengers,

“(D) mere scavengers

“(E) mere scavengers”

All right, we’ve got an X rather than Y comparison structure. We’re going to have to figure out what the X is and that will indicate what form we need to choose for the Y. (You may decide to jot down X rather than Y to remind yourself to address this issue.)

Time to Read the sentence! What’s it saying?

“The new image of Stone Age people as systematic hunters of large animals, rather than merely scavenging for meat, have emerged from the examination of tools found in Germany, including three wooden spears that archaeologists believe to be about 400,000 years old.”

Strip that down to the core:

The new image of (some) people as X, rather than Y, have emerged from the examination (of tools).

What do you notice?

Wait a sec: there’s an error in the core sentence! You can choose to stick with the original comparison issue, or you can switch gears and Work on the subject-verb issue first. I’m going to do the latter:

The new image have emerged.

No way! Image is singular, so it should say the new image has emerged. Say goodbye to answers (A) and (B).

Answers (C) through (E) are all okay on this point, so now loop back around. Luckily, we’ve already identified the second potential issue: that comparison.

The new image of (some) people as systematic hunters of large animals, rather than Y, have emerged from the examination (of tools).

X is hunters (of large animals), so Y should be in the same noun form. Hmm. This is another reason to get rid of (A) and (B), but (C) through (E) all use the proper match, scavengers.

Aside: I’m not thrilled with mere meat scavengers in (C). I’d prefer mere scavengers of meat, as in (D) and (E). But there isn’t a strong grammatical reason why I couldn’t use mere meat scavengers, so I’m going to ignore that and look for something else. Loop around again!

Now, when you’re down to a small number of choices, compare the remaining answers, looking for differences. There are a couple, but they’re all actually part of a big modifier, so I recommend looking at them as one big chunk:

“(C) … from examining tools found in Germany that includes

“(D) … from the examination of tools found in Germany, which includes

“(E) … from the examination of tools found in Germany, including”

The three structures at the end are used for three types of modifiers.

That includes, in (C), signals an essential noun modifier: the modifier must be included in the sentence or the basic meaning of the core sentence will be nonsensical.

Further, the noun should be as close as possible to the modifier. In this case, the noun Germany is right before the comma. Logically, the modifier should refer to tools. In certain circumstances, it is possible to have a short separation of the noun and the modifier—but is it okay in this case to say that the that includesmodifier refers back to tools, with a short found in Germany modifier in between?

Try it out:

… from the examination of tools that includes …

Oops. No, it’s not possible in this case because tools is plural and includes is singular. Logically, the modifier points to tools, but structurally it points to the singular Germany (or maybe even the singular examination?). None of these works; eliminate (C).

Can you use the same reasoning to eliminate either (D) or (E)?

Yes! Answer (D) changes the modifier to the non-essential structure comma which includes, and this modifier has the same problem: includes would have to be plural in order to point to tools. Eliminate (D).

But wait a second. Answer (E) doesn’t seem to be doing what it’s supposed to be doing either. It uses acomma –ing modifier:

The new image of (some) people as X, rather than Y, has emerged from the examination of tools found in Germany, including (some spears).

A comma –ing modifier refers back to the entire preceding clause, but is it really the case that the three spears refer back to the image has emerged from the examination?

We’ve just uncovered one of the few exceptions to the general comma –ing rule: when using the wordincluding, the sentence really can just be giving examples of something (usually a noun) that was named shortly before the comma. Unlike the modifiers in answers (C) and (D), the including modifier in (E) does not contain a verb that needs to match the noun tools, so there are no problems with the construction.

All right, are you ready to try out the GRW process on Critical Reasoning?

“According to the Tristate Transportation Authority, making certain improvements to the main commuter rail line would increase ridership dramatically. The authority plans to finance these improvements over the course of five years by raising automobile tolls on the two highway bridges along the route the rail line serves. Although the proposed improvements are indeed needed, the authority’s plan for securing the necessary funds should be rejected because it would unfairly force drivers to absorb the entire cost of something from which they receive no benefit.

“Which of the following, if true, would cast the most doubt on the effectiveness of the authority’s plan to finance the proposed improvements by increasing bridge tolls?

“(A) Before the authority increases tolls on any of the area bridges, it is required by law to hold public hearings at which objections to the proposed increase can be raised.

“(B) Whenever bridge tolls are increased, the authority must pay a private contractor to adjust the automated toll-collecting machines.

“(C) Between the time a proposed toll increase is announced and the time the increase is actually put into effect, many commuters buy more tokens than usual to postpone the effects of the increase.

“(D) When tolls were last increased on the two bridges in question, almost 20 percent of the regular commuter traffic switched to a slightly longer alternative route that has since been improved.

“(E) The chairman of the authority is a member of the Tristate Automobile Club that has registered strong opposition to the proposed toll increase.”

Try that problem out and we’ll talk about it next time!

Key Takeaways for Every Problem You Will Ever Do: (1) First, see whether a quick look can give you an early idea of what the question may be testing. On SC,glance at the word right before the underline and at the first word of the underline: any clue markers there? Next, compare the first word or two of each answer choice: do the differences signal any particular issues?

(2) Next, Reflect on what you’ve been given and Organize your thoughts. If you’re lucky, you’ll spot more than one potential issue to tackle. In that case, pick the issue that you think is the easiest or most straightforward.

(3) When you know you’ve got an error, cross off that answer choice and any others that repeat the same error. Once you’ve finished dealing with the first potential issue, you’ll likely still have more than one answer left, so it’s very useful if you came up with two ideas to start. Now you know exactly what you’re going to tackle next!

* GMATPrep® questions courtesy of the Graduate Management Admissions Council. Usage of this question does not imply endorsement by GMAC.

Stacey Koprince is a Manhattan Prep instructor based in Montreal, Canada and Los Angeles, California. Stacey has been teaching the GMAT, GRE, and LSAT for more than 15 years and is one of the most well-known instructors in the industry. Stacey loves to teach and is absolutely fascinated by standardized tests. Check out Stacey’s upcoming GMAT courses here

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ForumBlogs - GMAT Club’s latest feature blends timely Blog entries with forum discussions. Now GMAT Club Forums incorporate all relevant information from Student, Admissions blogs, Twitter, and other sources in one place. You no longer have to check and follow dozens of blogs, just subscribe to the relevant topics and forums on GMAT club or follow the posters and you will get email notifications when something new is posted. Add your blog to the list! and be featured to over 300,000 unique monthly visitors

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