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Whether you’re just beginning your studies or have been training for the GMAT for some time now, you likely have some idea of what your ‘goal score’ is. For many GMATers, the goal is 700+. That score is relatively rare territory though – only about 10% of Test Takers ever reach that level (and some of them actually hit that score repeatedly - in an attempt to score higher, so not as many Test Takers score 700+ each year as you might think). Obviously, the numbers become even more rare at higher levels. The 760+ level is essentially the 99th percentile. For simple comparison purposes, for every 1,000 people who take the GMAT this year, only about 10 of them will score 760+ (and some of those Test Takers are GMAT Teachers/Tutors or other industry experts who are not taking the GMAT with the intent to go to Business School).

The GMAT is a remarkably consistent Exam. It’s predictable – and you can train to properly face everything that will appear on Test Day. However, mere knowledge will not be enough to get you to a 760+. The GMAT is NOT an ‘IQ test’, nor is it a ‘math test’ or a ‘vocab test.’ At its core, it’s a ‘critical thinking test’, so to score at the highest levels, you have to look beyond having the necessary knowledge and general math/verbal abilities – and you have to train to ‘see’ (and respond to) the GMAT a certain way. A degree of flexibility is also required on your part; since GMAT questions can almost always be approached in more than one way, you have to learn multiple approaches (so that you can choose the most efficient approach for every question that you face).

This thread will help you to work on the very skills that can help you to score 760+.

GMAT Assassins aren’t born, they’re made, Rich

Edit: Note: If you have any questions about anything in this thread, then you can feel free to contact me directly via email or PM.

PAGE 1: 04/11/2017 Learning to Solve Quant Questions in More than Just One Way (part 1) (Jump to it) 04/11/2017 Learning to Solve Quant Questions in More than Just One Way (3 approaches) (Jump to it) 04/13/2017 Finding Patterns in PS Questions When You Don’t Immediately See Them (Jump to it) 04/19/2017 Test Your Pattern-Finding Skills on These 3 PS Questions (Jump to it) 04/22/2017 Solutions: The Patterns Behind those Prior 3 PS Questions (Jump to it)

04/30/2017 Acknowledge That “Your Way” is NOT Necessarily the Fastest Way (and Then CHANGE Your Approach) (Jump to it) 05/01/2017 Answer to the Prior Question: Long Math Approaches vs. Faster Tactical Approaches (Jump to it) 05/14/2017 Using the Answers in a PS Question to Your Advantage (Jump to it) 05/15/2017 Use the Answers to Your Advantage on These 3 Questions…. (Jump to it) 05/16/2017 Explanations to the Prior 3 Problem Solving Question…. (Jump to it)

05/23/2017 Reading Comp: Learning to Read GMAT RC at the Perfect Pace (Jump to it) 05/29/2017 Reading Comp: Practice Your Reading Pace on 3 Passages (Jump to it) 07/12/2017 Your Big Problem With the Verbal Section is Based on a “Probability Problem” (Jump to it) 08/14/2017 Defining Your Pacing Problem in the Quant and/or Verbal Sections (Part 1) (Jump to it) _________________

Learning to Solve Quant Questions in More than Just One Way (part 1)

The Quant section of the GMAT is NOT a ‘math test’ – it’s a ‘critical thinking test’ that uses math as the subject through which you can prove your critical thinking skills. While the Quant section does require that you complete lots of basic calculations as you work through the section, the GMAT will NEVER require that you complete complex calculations to get to the correct answer… so if you CHOOSE to approach questions in that way, then you will likely limit how high you can score. If one of your goals is a Q51, then you would find it really helpful to build up a multitude of Quant skills, instead of focusing on complex, long-winded ‘math approaches’ that often take longer to implement than other more-strategic options and increase the chances of you making little mistakes along the way.

The GMAC Official Guide is a fantastic book of practice questions – and if you don’t have a copy, then you should absolutely purchase one for your studies.

Consider the following question that appears in the Diagnostic Test of the GMAC Official Guide. It’s question #8 in the Problem Solving section of the Diagnostic – and has appeared in the last several versions of that book:

If a certain toy store’s revenue in November was 2/5 of its revenue in December and its revenue in January was ¼ of it’s revenue in November, then the store’s revenue in December was how many times the average (arithmetic mean) of its revenues in November and January?

1/4 1/2 2/3 2 4

This is a fairly mid-level prompt; it’s a little wordy but the ‘math’ behind it isn’t too difficult. How would you approach it? Would you use algebra? Do you recognize that there are at least two OTHER ways to get to the correct answer (and one of those approaches requires almost no math…)?

Take a moment to answer this question in whatever way you choose. Write everything down and – in the next post - we’ll compare your approach to the three options that I’ve hinted at.

GMAT Assassins aren’t born, they’re made, Rich

If you have any questions about anything in this thread, then you can feel free to contact me directly via email or PM.
_________________

Learning to Solve Quant Questions in More than Just One Way (3 approaches)

In the prior post, I hinted that there were (at least) 3 different approaches to solving the included OG Diagnostic question. Here they are:

1st Approach: Algebra

The explanations provided in the Official Guide often focus on the ‘math approach’ as that is that standard approach taken in most math books. However, that type of approach is often step-heavy and arguably takes the longest to complete.

For this prompt, we can create 3 variables:

N = revenue in November D = revenue in December J = revenue in January

With the information in the first half of the prompt, we can create two equations:

N = (2/5)(D) J = (1/4)(N)

We’re then asked to calculate (D) / [(N+J)/2]

With the given equations, we can translate each variable ‘in terms of’ D and plug in… Again, this is tedious, step-heavy work, but you can view it in the Official Guide if you like.

2nd Approach: TESTing VALUES

Many questions in the Quant section can be solved with a Tactical approach (and part of your training should focus on learning those approaches and when certain Tactics are applicable). Here, we are given no actual values to work with, so we can choose our own.

Based on the fractions involved, the common denominator would be 20, so let’s start with D = 20…

IF…. D = 20 then N = (2/5)(D) = 8 J = (1/4)(N) = 2

Now, we just have to place D = 20, N = 8 and J = 2 into the question….

(20) / [(8 + 2)/2] = (20) / (5) = 4

This is the answer to the question - and you’ll get that same result regardless of the values that you choose to TEST (as long as your numbers ‘fit’ the given equations). This approach has the benefit of being fast and easy (consider the work involved - we’re really just adding and multiplying small numbers together). With fewer steps, you’re also less likely to make a little mistake along the way.

3rd Approach: Logic (and using the ‘spread’ of the answers to your advantage)

Certain questions in the Quant section are designed with really fast ‘concept shortcuts’ in mind. This is done on purpose to reward strong critical thinkers. Business Schools are looking for EXACTLY that type of critical-thinking applicant, but the GMAT has no way to give you extra points for ‘being clever’ – it can only provide you with potential shortcuts that will save you time and decrease whatever pacing-related anxiety that you might have. As a result of finding these shortcuts, your chances of scoring higher should increase, since you’ll have more time to answer the remaining questions than someone who is using lengthy math approaches and losing time as a result.

Here, consider how the given monthly revenues relate to one another….

1 - November’s revenue is 2/5 of December’s revenue. This means that the December revenue is MORE THAN DOUBLE November’s revenue.

2 – January’s revenue is ¼ of November’s revenue. Since January’s revenue is so much smaller than November’s revenue – and we already know that December’s revenue is MORE THAN DOUBLE November’s revenue, then this means that December’s revenue is a LOT greater (FAR MORE than double) than January’s revenue.

We’re asked to compare December’s revenue to the AVERAGE of November’s and January’s…. Averaging those two smaller numbers will lead to a result that is SMALLER than November's. By extension December’s revenue will be far GREATER than double than average. Looking at the answer choices, there’s only one answer that fits that description…. 4.

Now, consider how much actual work went into the 2nd and 3rd approaches to this prompt (especially relative to the work that went into the 1st approach). Assuming that you had an equal ability to tackle this question using all 3 approaches, which one would be fastest and easiest to implement? If you’re training to be a 760+ Assassin, then you know that it’s NOT the 1st approach.

GMAT Assassins aren’t born, they’re made, Rich

If you have any questions about anything in this thread, then you can feel free to contact me directly via email or PM.
_________________

Finding Patterns in PS Questions When You Don’t Immediately See Them

Since the GMAT is a standardized Test, all of the questions that you’ll face are designed around one or more patterns. Sometimes the patterns are obvious – such as math formulas or grammar rules. Sometimes the patterns are more subtle - such as number properties or causality arguments.

With the proper study materials and Study Plan, you can learn all of the necessary patterns and train to properly use them. However, sometimes the patterns are so rare that they’re not worth learning in advance and sometimes they are essentially ‘hidden’, meaning that you won’t immediately see the pattern involved. However, the pattern is still there – and correctly answering some of the tougher questions on the GMAT will be considerably easier IF you are comfortable with the idea that you can ‘play around’ with the prompt a bit and define what the pattern is.

“Playing around” with a GMAT question is essentially about running little ‘experiments’ on it. In basic terms, you need to ask “what if….?” and then go about determining the result.

For example, here is a question from the PS Forums here. Your immediate task is NOT to calculate the result – it’s to figure out the first 4 terms in the sequence and THEN deduce a pattern within those 4 terms….

For every integer K from 1 to 10, inclusive, the Kth term of a certain sequence is given by:

[(-1)^(K+1)] x [1/(2^K)].

If T is the sum of the first 10 terms in the sequence, then T is….

A. Greater than 2 B. Between 1 and 2 C. Between 1/2 and 1 D. Between 1/4 and 1/2 E. Less than 1/4

So… what have you deduced? The answer appears below:

The first four terms are: +1/2, - 1/4, + 1/8, - 1/16. Thus, the terms ‘flip-flop’ between positive and negative. In addition, each negative term, when ‘paired’ with the positive term immediately ahead of it, cuts the positive term in half…

+1/2 – 1/4 = +1/4 +1/8 – 1/16 = +1/16

Now that you recognize this pattern, you should be able to quickly determine the value of the other three ‘pairs’:

They get progressively smaller: +1/64, +1/256, +1/1024

The question asks for the sum of the first 10 terms, but doesn’t provide exact answers – it provides RANGES, so you do NOT have to be exact with your math. To answer this question, you really just have to ask...

What are we really adding to +1/4? A bunch of increasingly shrinking (and significantly small) fractions. Thus, the sum has to be….

A little more than 1/4. Final Answer: D

In the next post, I’ll list a few additional PS prompts for you to ‘play around’ with. Remember the immediate goal – decipher the pattern first. Then, use whatever pattern you discover to answer the question.

GMAT assassins aren’t born, they’re made, Rich

If you have any questions about anything in this thread, then you can feel free to contact me directly via email or PM.
_________________

Test Your Pattern-Finding Skills on These 3 PS Questions

For each of these three prompts, you should attempt to ‘play around’ with the question to define the pattern(s) involved – using the same approach showcased in the prior post. An explanation for how to approach each prompt in such a way will be provided in the next post.

1) How many positive integers, from 2 to 100, inclusive, are not divisible by odd integers greater than 1?

A. 5 B. 6 C. 8 D. 10 E. 50

2) There are 20 doors marked with numbers 1 to 20 and there are 20 individuals marked 1 to 20.

An operation on a door is defined as changing the status of the door from open to closed or vice versa. All doors are closed to start with.

One at a time, one randomly picked individual goes and operates the doors. The individual operates only those doors which are a multiple of the number he/she is carrying. For example, the individual marked with the number 5 only operates the doors marked with the following numbers: 5, 10, 15 and 20.

If every individual in the group gets one turn, then how many doors are open at the end?

A. 0 B. 1 C. 2 D. 4 E. 6

3) A test has 200 questions. Each question has 5 options, but only 1 option is correct. If test-takers mark the correct option, then they are awarded 1 point. However, if an answer is incorrectly marked, the test-taker loses 0.25 points. No points are awarded or deducted if a question is not attempted. A certain group of test-takers attempted different numbers of questions, but each test-taker still received the same net score of 40. What is the maximum possible number of such test-takers?

A. 31 B. 33 C. 35 D. 40 E. 42

GMAT assassins aren’t born, they’re made, Rich

If you have any questions about anything in this thread, then you can feel free to contact me directly via email or PM.
_________________

Solutions: The Patterns Behind those Prior 3 PS Questions

While each of these three prompts might look complex, you CAN get to the correct answer by defining the patterns involved.

1) How many positive integers, from 2 to 100, inclusive, are not divisible by odd integers greater than 1?

In this prompt, we're asked to think about the numbers 2 to 100, inclusive. To start, there's NO way that the GMAT would ask us to truly think about each of these numbers individually, so there MUST be a pattern involved.

Now to the specifics: which of these numbers are NOT divisible by an odd integer that is greater than 1???

Let's start at the first number and work our way "up" until the pattern becomes clear:

2 - this is NOT divisible by any odd integers, so this "fits" what we're looking for... 3 - this IS divisible by an odd integer (3), so it's out 4 - this is NOT divisible by any odd integers, so this "fits" 5 - this IS divisible by an odd integer (5), so it's out 6 - this IS divisible by an odd integer (3), so it's out 7 - this IS divisible by an odd integer (7), so it's out 8 - this is NOT divisible by any odd integers, so this "fits"

Now, looking at the numbers that "fit", we have 2, 4 and 8.....that's 2^1, 2^2 and 2^3....that MUST be the pattern involved, so we can use this knowledge against the rest of the question to find the other values that "fit": 2^4 = 16 2^5 = 32 2^6 = 64 2^7 = 128, but that's outside the range that we were given. Thus, there are 6 values that "fit" what we're looking for.

2) There are 20 doors marked with numbers 1 to 20. And there are 20 individuals marked 1 to 20. An operation on a door is defined as changing the status of the door from open to closed or vice versa. All doors are closed to start with. Now one at a time one randomly picked individual goes and operates the doors. The individual however operates only those doors which are a multiple of the number he/she is carrying. For e.g. individual marked with number 5 operates the doors marked with the following numbers: 5, 10, 15 and 20. If every individual in the group gets one turn, then how many doors are open at the end?

It would take a LOT of time to work through all 20 people and all 20 doors, so I'm going to work through the first several so that we can define the pattern involved...

Remember: All the doors start off CLOSED... Door 1: Only Person 1 touches this door. So it IS OPEN at the end. Door 2: Person 1 and Person 2 touch this door. So it is closed at the end. Door 3: Person 1 and Person 3 touch this door. So it is closed at the end. Door 4: Person 1, 2 and 4 touch this door. So it IS OPEN at the end.

Now, stop and look at the work that we've done so far... Which doors do we know for sure will be open? Door 1 and Door 4. What do those two numbers have in common? They're both PERFECT SQUARES..... Let's see if that pattern continues...

Door 5: Person 1 and 5 touch this door. CLOSED. Door 6: Person 1, 2, 3 and 6 touch this door. CLOSED. Door 7: Person 1 and 7. CLOSED. Door 8: Person 1, 2, 4 and 8. CLOSED Door 9: Person 1, 3 and 9. OPEN.

Notice how the next door that we know will be open in the end is Door 9. It is ALSO a PERFECT SQUARE. Given the work we've done so far, this MUST be the pattern, so we're ultimately looking for the number of perfect squares from 1 to 20. They are 1, 4, 9 and 16. That's a total of 4 open doors at the end.

3) A test has 200 questions. Each question has 5 options, but only 1 option is correct. If test-takers mark the correct option, then they are awarded 1 point. However, if an answer is incorrectly marked, the test-taker loses 0.25 points. No points are awarded or deducted if a question is not attempted. A certain group of test-takers attempted different numbers of questions, but each test-taker still received the same net score of 40. What is the maximum possible number of such test-takers?

From the answer choices, we can see that there are a lot of different ways to get a total of 160 points (at least 31 ways...), so there's no way that the GMAT would require that we calculate each individual option. There has to be a pattern, so let's start off with the easiest 'ways' to get 160 points and go from there... Remember - a correct answers get you 1 point, an incorrect answer gets you MINUS 1/4 point and a skipped question gets you 0 points. So, how can we get 160 points...

To find all of the options, you can either "count up" (40+0 = 40, 41+4 =45, 42+8 = 50, etc.) OR you can "count down" from the number of skipped questions. (160, 155, 150, etc.). With either option, you'll eventually run out of questions, then you'll be done.

Counting down from 160 is probably faster, as long as you don't forget the final option - the one with 0 skipped questions). Here, there are 33 multiples of 5 (including the 0 'option').

As you continue to study, it's important to remember that most GMAT Quant questions are NOT 'testing' your knowledge of advanced math, specialty formulas or complex ideas. The 'math' behind most Quant questions is actually rather straight-forward. As such, to maximize your score, you have to be ready to 'play around' with 'tough-looking' prompts and find the simple math behind them.

GMAT assassins aren’t born, they’re made, Rich

If you have any questions about anything in this thread, then you can feel free to contact me directly via email or PM.
_________________

Acknowledge That “Your Way” is NOT Necessarily the Fastest Way (and Then CHANGE Your Approach).

The GMAT is a remarkably consistent and predictable Exam, so improving your performance isn’t just about ‘fixing’ the things that you are doing ‘wrong’ – it’s also in developing the proper skills to improve on work that you can already do.

Consider the following question. For many “math thinkers”, the approach would be “system algebra” – write out the appropriate equations and then solve for whatever the question asks for. That approach will absolutely get you to the correct answer here – and I suggest that you try it. Make sure to time yourself though - we need to know how long it would take you to solve this question using an algebraic approach.

Andrew has a certain number of coins in his pocket. He has three times as many dimes as quarters and six times as many nickels as dimes. A nick is worth $0.05, a dime is worth $0.10 and a quarter is worth $0.25. If he has a total of $10.15, then which of the following represents the number of dimes in Andrew’s pocket?

How long did it take you? For most GMATers, this question would require 2-3 minutes (or more) of work. If you’re really great at algebra, it might take you less time than that.

Now, I bet that I can show you a MUCH faster way to get to the correct answer – and it’s an approach that you’ll be able to use 2-3 times on the Official GMAT. Tomorrow, I’ll show you how it works and how to use it.

GMAT assassins aren’t born, they’re made, Rich

If you have any questions about anything in this thread, then you can feel free to contact me directly via email or PM.
_________________

Answer to the Prior Question: Long Math Approaches vs. Faster Tactical Approaches

In the prior post, I listed the following Quant PS question:

Andrew has a certain number of coins in his pocket. He has three times as many dimes as quarters and six times as many nickels as dimes. A nick is worth $0.05, a dime is worth $0.10 and a quarter is worth $0.25. If he has a total of $10.15, then which of the following represents the number of dimes in Andrew’s pocket?

9 10 18 20 21

Many GMATers will approach these types of questions algebraically, even though that type of approach often takes longer than other, faster, more strategic options.

The Long Math:

To start, here is how you can solve this algebraically. Let’s use the following variables:

N = number of nickels D = number of dimes Q = number of quarters

The second sentence allows us to create two equations using the above variables:

D = 3Q N = 6D

The third and fourth sentences allow us to create a third equation:

(.05)N + (.10)D + (.25)Q = 10.15

Now we have a ‘system’ of equations – three variables and three unique equations, so we can solve for each of the individual variables. The prompt asks us to determine the number of DIMES, so I’ll focus the work on solving for D.

D = 3Q …. Q = D/3 N = 6D

Substituting in for N and Q, we end up with…

(.05)(6D) + (.10)(D) + (.25)(D/3) = 10.15

.3D + .1D + (.25D/3) = 10.15

We can now multiply everything by 3 to get rid of the fraction…

Now, consider ALL of the work that I just did. Even if you took a slightly different approach to the algebra, how long would all of this work take…? Two minutes? Three minutes? Longer?

Instead, let’s use the ‘design’ of the GMAT to our advantage. Here, the answer choices ARE numbers, and we’re asked to solve for just one variable (the number of dimes), so let’s TEST THE ANSWERS.

Faster Tactics:

To start, we’re told that the number of dimes is 3 TIMES the number of quarters, so the number of dimes MUST be a MULTIPLE OF 3. That helps us to immediately eliminate answers B and D (since 10 and 20 are NOT multiples of 3).

Let’s TEST Answer C: 18. If it’s the correct answer, then we’ll be done. If it’s “too high” or “too low”, then we’ll know exactly which of the remaining two answers is the correct one.

IF… there are 18 dimes Then there are 6 quarters (since there are three times as many dimes as quarters) and there are 108 nickels (since there are 6 times as many nickels as dimes).

Given the respective values of the three coins, we would have a total of….

However, we were told that the actual total value of the coins is $10.15. This total ($8.70) is TOO LOW, which means that we need there to be more nickels, dimes and quarters. There’s only one answer left that ‘fits’ what we’re looking for, so that MUST be the correct answer!

At this point, you have to be honest with yourself. Which approach was faster and easier? Even if you “love” doing formal math, taking that approach can only lead to problems later on (especially if you have pacing issues or are prone to making little mistakes when you have to do a lot of work). The Tactical approach here (TESTing ANSWERS) is faster, easier and requires less overall work. GMATers who score at the highest levels know when to use this approach and how to properly use this approach (and the basic ideas behind this Tactic can also help you solve certain Verbal questions as well) so there are multiple benefits to mastering it.

GMAT assassins aren’t born, they’re made, Rich

If you have any questions about anything in this thread, then you can feel free to contact me directly via email or PM.
_________________

Using the Answers in a PS Question to Your Advantage

In a couple of prior posts in this thread – (Here) and (Here) - we’ve discussed how to taking advantage of the answer choices (by TESTing THE ANSWERS or by thinking about what the answers choices 'mean') can be a really fast and easy way to get to the correct answer in certain Quant questions. Beyond using the answers and doing the straight-forward arithmetic though, you will sometimes be given a HUGE ‘hint’ from the GMAT question writers – the answer choices themselves will be designed in such a way that you can avoid doing a lot of math altogether. One of the ‘keys’ to spotting (and using) those shortcuts is to be on the lookout for quirky clues in the wording of the prompt.

Consider the following question:

A motorist averaged 40 miles per hour on his way to work. He averaged 70 miles per hour on his way home along the same route. Which of the following is the closest to his average speed for the round trip?

Now, let’s discuss the shortcut I alluded to earlier…

This prompt is a fairly common 'design' for a Weighted Average question. Here, a motorist travels a certain distance at one speed, then travels back - the SAME distance - at a different speed. We're asked for the AVERAGE SPEED for the entire trip.

One of the key elements to these types of questions is that the answer will be closer to the slower speed than to the faster speed. The exact 'middle' between 40 and 70 is 55, BUT since the motorist spends MORE time driving 40 mph, the average would have to be closer to 40 (while not being 40 exactly). Given the available answer choices, there's only one answer that 'fits'...

The 'takeaway' from all of this: when approaching GMAT questions, the best Test Takers use ALL of the information that they've been given - including whatever is in the five answer choices.

Tomorrow, I’ll provide 3 additional prompts that you can solve by taking advantage of the answer choices.

GMAT assassins aren’t born, they’re made, Rich

If you have any questions about anything in this thread, then you can feel free to contact me directly via email or PM.
_________________

Use the Answers to Your Advantage on These 3 Questions….

Each of the three questions listed here can be solved algebraically. However, if you pay attention to the five answer choices in each question, then you can cut down on the amount of work that is needed and potentially save some time. Remember that the goal on Test Day is to be correct AND be efficient, so while a shortcut that saves 5-10 seconds might not seem like much, if you could find that type of shortcut on every question, then you would cut 3-7 minutes of work-time in each section.

1) A motorist averaged 40 miles per hour on his way to work. He averaged 70 miles per hour on his way home along the same route. Which of the following is the closest to his average speed for the round trip?

2) Franny can type 80 words per minute and Matt can type 60 words per minute. If the two together must type up a 14,000-word paper and each person can type for at most 2 hours, what is the least amount of time, in hours, that Matt must type?

3) At a company meeting, M men and W women meet in a conference room. If there are twice as many men as women at the meeting and the conference room can hold no more than 50 total people, then what is the maximum number of women who can be at that meeting?

Explanations to the Prior 3 Problem Solving Question….

1) A motorist averaged 40 miles per hour on his way to work. He averaged 70 miles per hour on his way home along the same route. Which of the following is the closest to his average speed for the round trip?

The answers to this question are 'spaced out' in such a way that you don't need to do much math at all to get to the correct answer. This prompt is a fairly common 'design' for a Weighted Average question. Here, a motorist travels a certain distance at one speed, then travels back - the SAME distance - at a different speed. We're asked for the AVERAGE SPEED for the entire trip.

One of the key elements to these types of questions is that the answer will be closer to the slower speed than to the faster speed. The exact 'middle' between 40 and 70 is 55, BUT since the motorist spends MORE time driving 40 mph, the average would have to be closer to 40 (while not being 40 exactly). There's only one answer that 'fits'...

---------------

2) Franny can type 80 words per minute and Matt can type 60 words per minute. If the two together must type up a 14,000-word paper and each person can type for at most 2 hours, what is the least amount of time, in hours, that Matt must type?

The answer choices to this question provide a really nice 'shortcut' that can help you to cut down on the amount of math that is necessary to answer this question. To start, we're told that Franny and Matt can each type UP TO 2 hours, but we're asked for the LEAST amount of time (in hours) that Matt would need to type. Thus, the answer is almost certainly going to be LESS than 2. Eliminate Answer A and Answer E (this answer is almost 4 hours, which is simply not an option based on the information in the prompt).

Given Franny's rate (80 words/minute), we know that in 2 hours she would type (2)(60)(80) = 9600 words. This leaves 14,000 - 9,600 = 4,400 words for Matt.

Given Mat's rate (60 words/minute), the 4400 words would take 4400/60 = OVER 60 minutes. You don't need to calculate the exact value - it's enough to note that Matt would need to spend MORE than 1 hour typing. Answers B and C are LESS than 1 hour, so there's only one answer that makes sense...

---------------

3) At a company meeting, M men and W women meet in a conference room. If there are twice as many men as women at the meeting and the conference room can hold no more than 50 total people, then what is the maximum number of women who can be at that meeting?

This question can be approached Algebraically or by TESTing THE ANSWERS. Here is how you can get to the solution by TESTing THE ANSWERS.

We're given a couple of facts to work with: 1) There are TWICE as men as women in a conference room 2) The conference room can hold UP TO 50 people.

We're asked for the MAXIMUM number of WOMEN that the room can hold.

Let's TEST Answer D: 18 women IF... there were 18 women, then there would be 2(18) = 36 men. 18 + 36 = 54, but that is TOO MANY people (the room can only hold up to 50), so this answer is TOO BIG. Eliminate D and E (that answer would be even BIGGER).

Answer C: 17 women IF... there were 17 women, then there would be 2(17) = 34 men. 17 + 34 = 51, but that is TOO MANY people (although it's REALLY close), so this answer is TOO BIG. Eliminate C.

Answer B: 16 women IF... there were 16 women, then there would be 2(16) = 32 men. 16 + 32 = 48. This is the LARGEST answer that 'fits' all of the information that we've been given, so this MUST be the answer.

---------------

As you continue to study, remember to use EVERY piece of information that each prompt gives you. This idea is relevant in BOTH the Quant and Verbal sections - and is 'key' to maximizing your performance on Test Day.

GMAT assassins aren’t born, they’re made, Rich

If you have any questions about anything in this thread, then you can feel free to contact me directly via email or PM.
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Reading Comp: Learning to Read GMAT RC at the Perfect Pace

Many GMATers make the mistake of thinking that ‘skimming’ is the proper way to deal with Reading Comp passages. By its nature, skimming is often a desperate way of trying to quickly deal with a (frequently lengthy) passage. Unfortunately, it sacrifices all manner of comprehension and note-taking for speed. That is a TERRIBLE trade-off – and often causes serious problems for Test Takers as they practice RC during their studies. By extension, those same Test Takers often fail to perform at a really high level on RC on Test Day, which keeps them from scoring at a really high level overall.

Proper reading speed for GMAT Reading Comp is probably not what you think it should be. As an experiment, we’re now going to test YOUR natural reading speed.

Here is an RC passage from the Diagnostic Test of the OG, formatted in the same way that it appears in that book. We’re not going to focus on answering the questions; this is just about reading the prompt. For this exercise, I want you to keep track of how long it takes you to complete the passage (and you should try to mimic your typical reading speed when you take your practice CATs). We’re going to use that piece of information to assess your default way of dealing with RC.

All right. Ready? Start your timer and begin…

Women’s grassroots activism and their vision of a new civic consciousness lay at the heart of social reform in the United States throughout the Progressive Era, the period between the depression of 1893 and America’s entry into the Second World War. Though largely disenfranchised except for school elections, white middle-class women reformers won a variety of victories, notably in the improvement of working conditions, especially for women and children. Ironically, though, child labor legislation pitted women of different classes against one another. To the reformers, child labor and industrial home work were equally inhumane practices that should be outlawed, but, as a number of women historians have recently observed, working-class mothers did not always share this view. Given the precarious finances of working-class families and the necessity of pooling the wages of as many family members as possible, working-class families viewed the passage and enforcement of stringent child labor statutes as a personal economic disaster and made strenuous efforts to circumvent child labor laws. Yet reformers rarely understood this resistance in terms of the desperate economic situation of working- class families, interpreting it instead as evidence of poor parenting. This is not to dispute women reformers’ perception of child labor as a terribly exploitative practice, but their understanding of child labor and their legislative solutions for ending it failed to take account of the economic needs of working-class families.

How much time did you spend? Be honest.

0 – 40 seconds: You’re either amazing at RC or probably really terrible at it. Since you’re reading this article, it’s probably the latter. The time that you would have spent rushing through this prompt has been wasted. You will almost certainly need to go back to reread the prompt repeatedly as you work through the questions – and that’s a big waste of overall time and effort.

41 – 65 seconds: You may have caught some of the ideas/meaningful words in the prompt, but you probably won’t be able to accurately summarize them and you’ll end up rereading the prompt each time you have to deal with a new question about it.

66 – 89 seconds: Depending on your level of comprehension, you might have absorbed some of what’s here. What’s the point of the article? What is the article really discussing? Does the author have an opinion on the subject matter? At this speed, you probably missed out on some of the relevant points that were made, so most of the questions will require that you reread the prompt.

90 - 100 seconds: Proper reading speed for Reading Comp on the GMAT is about 150 words per minute. This prompt is roughly 230 words, so if you engaged with the prompt, then this is just about the perfect amount of time for this passage. Any ‘detail’ questions will require that you reread a small section of the prompt (but that’s often the case for those types of questions regardless of the length of the prompt or the subject matter).

101 – 120 seconds: Not too bad. You might have gotten hung up on some of the vocabulary, but you didn’t let it keep you from moving on to the parts of the passage that did understand.

121 – 140 seconds: We’re now getting to a point in which you’re probably rereading small chunks of the passage. You’re allowing yourself to get distracted by dense sentences and big vocabulary – and almost none of that will be relevant when it comes time to answering the questions.

141+ seconds: You might have broader ‘comprehension issues’, or you’re reading each sentence more than once. Training to learn what ‘matters’ in a passage and what doesn’t matter will be essential for you to score at a high level in the Verbal section.

Adapting one’s reading speed and ‘default way’ of reading is one of the specific challenges that most GMATers face. Since many of those habits are ingrained – they can take some serious time and commitment to change (you’ve been reading this way for most of your life, so you have to embrace the training if you want to improve). Thankfully, the style and logic behind GMAT RC is remarkably predictable – as are the question types and common wrong answers to RC questions – so you CAN train to score at a higher level. If your current study materials aren’t helping you to make those improvements, then it might be time to invest in materials that will.

GMAT assassins aren’t born, they’re made, Rich

If you have any questions about anything in this thread, then you can feel free to contact me directly via email or PM.
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Reading Comp: Practice Your Reading Pace on 3 Passages

In the prior post, we discussed proper reading pace for when you deal with GMAT RC passages (as a reminder, that pace should be about 150 words per minute). Unfortunately, simply knowing that fact won’t necessarily lead you to adjust your reading speed. So here are three practice prompts – taken from the OG12 – for you to practice on. Use a timer and make sure to note how long it took you to read each passage. The proper (goal) amount of reading time is listed in inviso-text beneath each prompt.

Passage 1:

Traditionally, the first firm to commercialize a new technology has benefited from the unique opportunity to shape product definitions, forcing followers to adapt to a standard or invest in an unproven alternative. Today, however, the largest payoffs may go to companies that lead in developing integrated approaches for successful mass production and distribution.

Producers of the Beta format for videocassette recorders (VCRs), for example, were first to develop the VCR commercially in 1975, but producers of the rival VHS (Video Home System) format proved to be more successful at forming strategic alliances with other producers and distributors to manufacture and market their VCR format. Seeking to maintain exclusive control over VCR distribution, Beta producers were reluctant to form such alliances and eventually lost ground to VHS in the competition for the global VCR market.

Despite Beta's substantial technological head start and the fact that VHS was neither technically better nor cheaper than Beta, developers of VHS quickly turned a slight early lead in sales into a dominant position. Strategic alignments with producers of prerecorded tapes reinforced the VHS advantage. The perception among consumers that prerecorded tapes were more available in VHS format further expanded VHS's share of the market. By the end of the 1980s, Beta was no longer in production.

A recent study has provided clues to predator-prey dynamics in the late Pleistocene era. Researchers compared the number of tooth fractures in present-day carnivores with tooth fractures in carnivores that lived 36,000 to 10,000 years ago and that were preserved in the Rancho La Brea tar pits in Los Angeles. The breakage frequencies in the extinct species were strikingly higher than those in the present-day species.

In considering possible explanations for this finding, the researchers dismissed demographic bias because older individuals were not over represented in the fossil samples. They rejected preservational bias because a total absence of breakage in two extinct species demonstrated that the fractures were not the result of abrasion within the pits. They ruled out local bias because breakage data obtained from other Pleistocene sites were similar to the La Brea data. The explanation they consider most plausible is behavioral differences between extinct and present-day carnivores—in particular, more contact between the teeth of predators and the bones of prey due to more thorough consumption of carcasses by the extinct species.

Such thorough carcass consumption implies to the researchers either that prey availability was low, at least seasonally, or that there was intense competition over kills and a high rate of carcass theft due to relatively high predator densities.

Many United States companies have, unfortunately, made the search for legal protection from import competition into a major line of work. Since 1980 the United States International Trade Commission (ITC) has received about 280 complaints alleging damage from imports that benefit from subsidies by foreign governments. Another 340 charge that foreign companies “dumped” their products in the United States at “less than fair value.” Even when no unfair practices are alleged, the simple claim that an industry has been injured by imports is sufficient grounds to seek relief.

Contrary to the general impression, this quest for import relief has hurt more companies than it has helped. As corporations begin to function globally, they develop an intricate web of marketing, production, and research relationships. The complexity of these relationships makes it unlikely that a system of import relief laws will meet the strategic needs of all the units under the same parent company.

Internationalization increases the danger that foreign companies will use import relief laws against the very companies the laws were designed to protect. Suppose a United States-owned company establishes an overseas plant to manufacture a product while its competitor makes the same product in the United States. If the competitor can prove injury from the imports—and that the United States company received a subsidy from a foreign government to build its plant abroad—the United States company’s products will be uncompetitive in the United States, since they would be subject to duties.

Perhaps the most brazen case occurred when the ITC investigated allegations that Canadian companies were injuring the United States salt industry by dumping rock salt, used to de-ice roads. The bizarre aspect of the complaint was that a foreign conglomerate with United States operations was crying for help against a United States company with foreign operations. The “United States” company claiming injury was a subsidiary of a Dutch conglomerate, while the “Canadian” companies included a subsidiary of a Chicago firm that was the second-largest domestic producer of rock salt.

Good GMAT ‘habits’ take time to hone, so you have to continue to train at this proper reading speed. Combined with the proper note-taking and Tactical knowledge about RC question types (and the types of common wrong answers that often appear), you’ll find that dealing with any passage – regardless of length or subject matter – will become a standard process.

GMAT assassins aren’t born, they’re made, Rich

If you have any questions about anything in this thread, then you can feel free to contact me directly via email or PM.
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Your Big Problem With the Verbal Section is Based on a “Probability Problem”

Many Test Takers tend to find the Quant section of the GMAT to be easier than the Verbal section. Quant is based on more ‘obvious’ rules and patterns and you can often pinpoint the correct answer without having to consider (and then eliminate) each of the other 4 incorrect answers first.

By default, many GMATers work through Verbal questions with the idea that they should eliminate the four incorrect answers… and the answer that remains will be the correct one. While you should often be able to eliminate a couple of ‘obvious’ wrong answers from each Verbal question (even if you don’t know what the correct answer actually is), if THAT is how you handle every Verbal question, then there is a BIG problem with your overall approach - and you’re probably limiting how high you will score in the Verbal section.

The big issue here is ultimately a “math” problem. If you consistently narrow the answers down to two choices (the correct one and one of the four incorrect ones), then probability dictates that you will likely answer just half of those questions correctly. While you can certainly afford to miss lots of hard/weird questions and still score at a high level, you cannot afford to miss HALF of the 41 Verbal questions and still expect to earn a high score. Without having the proper content knowledge and Tactical abilities, you’ll effectively be “winging it” through the Verbal section – and the GMAT doesn’t often reward that type of approach with a 700+ score.

Knowing all of this, you now have to define how much this issue actually applies to YOU… but you’ll have to put in the necessary work to analyze your CATs. Starting with your most recent CAT, you have to review each Verbal question AND your notes for each question. We need to know how many questions you “narrowed down to 2 choices” (ALL questions, regardless of whether you got the question correct or incorrect). You have to be honest with this assessment – if you didn’t “know” what you were looking for when you worked your way through the answers, then you were essentially trying to ‘eliminate your way’ to the correct answer.

It’s worth noting that some GMATers are naturally strong in the Verbal section – the questions just “make sense” to those Test Takers, so they don’t need a more formal process for dealing with the Verbal section. Since you’re reading this post though, then you are probably not one of those people. So, how many of the 41 questions did you deal with during your last CAT by narrowing the answers down to 2 choices?

0-10 questions: You either really know what you’re doing (and scoring at a really high level) or you have no idea what you’re doing and you’re misinterpreting most of the questions that you’re dealing with.

11-15 questions: You’re probably performing above average overall, but you’re missing out on enough points that you still have some work to do to get to the 700+ level.

16 – 20 questions: You’re unsure of how to handle almost half of the questions, which means that you’re missing serious points in at least 2 of the 3 major Verbal categories (SC, RC and CR). At this level, you might not be clear on what you actually have to do to correctly answer certain questions.

21 – 25: questions: “Your way” of dealing with the Verbal section is likely problematic and you will almost certainly need to invest in some new study materials and focus on learning/practicing proper Verbal Tactics to score higher.

26 – 30 questions: You’re almost certainly losing serious points in all 3 major Verbal categories (SC, RC and CR) and simply doing more practice questions will NOT get you to your score goal.

31 – 41 questions: Your work across most of the Verbal section is imprecise and you’ll need to invest a significant amount of time, money and energy to raise your Verbal score up to a high score level.

Regardless of how you’re performing now, it’s important to remember that the Verbal section of the GMAT is just as consistent and predictable as the Quant section is, so you CAN train to score at a higher level. The key word there is “train” – you cannot expect to just work your way through 100s of additional practice questions on your own and hope to hit your goal score. You will need help, so you have to do the necessary research and invest in some new practice materials and Tactics.

GMAT assassins aren’t born, they’re made, Rich

If you have any questions about anything in this thread, then you can feel free to contact me directly via email or PM.
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Defining Your Pacing Problem in the Quant and/or Verbal Sections (Part 1)

Over the years, one of the most common concerns that I’ve heard from GMATers is about their pacing – specifically, the fact that they have to rush through a number of questions at the end of a section just to finish on time. “How do I fix my pacing problem?” they ask (and you might be asking it too!).

First, you have to understand that a pacing problem doesn’t exist on its own – it’s the result of OTHER issues. In simple terms, something about how you handle the Quant and/or Verbal sections is CAUSING this pacing issue. To better define that cause (or causes), we have to analyze how you’re handling questions on your CATs. To properly do that, we need to look at one of your recent CATs and your NOTES for that CAT.

Certain practice CATs include information on how much time you spent on each question – and we need a CAT result that includes that information. THAT data is remarkably important, but we need more than just some numbers to solve your pacing issue. We also need to see what you wrote down, the ‘steps’ that you went through to try to answer each question, etc. For review purposes, you should always keep your notes from each CAT. At the very least, you’ll be able to reattempt questions that you originally got wrong. – which is a great way to measure your progress as you study and define how well you are improving. In addition, you can go back and see how you successfully answered certain questions (as those Tactics and patterns will likely be helpful on future questions.) At deeper levels, you can define WHY you got questions wrong in the first place – and that information can help you to change your tactics, improve your work and hone your skills.

QUANT

“On a CAT, no Quant question is worth more than 3 minutes of your time - not even the first question.”

Say that quote out loud. Right now. Then say it again. I don’t care where you are (and I don’t care if anyone looks at your strangely). Say it a third time. Now start living by that rule.

Believe it or not, 75 minutes IS enough time to work through the Quant section, but NOT if you’re making silly mistakes (that you then have to go back and fix) or wasting time by staring at the screen and hoping that an idea comes to you.

If you had to rush through even a couple of questions at the end of the Quant section, then you ‘over-committed’ to certain questions earlier on and wasted a bunch of time. If you have a pacing issue in the Quant section, then here’s what we have to specifically look for in your CAT results:

1. Count up the number of times that you spent 3 or more minutes on a question. Write all of those ‘times‘ down in a row. 2. What fraction of those questions did you get WRONG? Circle the times associated with the ones that you got wrong.

Over time, for most GMATers, the long-term fraction of wrong answers on questions that took 3+ minutes is about ½… meaning that when you spend THAT much time on a Quant question, there’s a really good chance that you’re going to get that question WRONG anyway! So in addition to getting a bunch of questions wrong, you end up wasting a bunch of time AND you end up not having enough time for the questions at the end of the section (which you mostly get wrong too). In effect, you’re getting killed twice for the same mistake… so you need to stop making that initial mistake. To figure out how to do that, we have to start with your notes…

3. Take a look at your notes for the first question from your list of “3+ minutes” questions. If you were to hand that section of your notes to someone else, would that person be able to answer the following questions:

A) What information did the prompt include? B) What question were you attempting to answer? C) What ‘steps’ did you go through? D) Were the numbers that you wrote down “labeled”?

If any of those 4 questions cannot be answered, then you’ve defined the first (and probably the BIGGEST) issue – you don’t take the proper notes. The GMAT will NEVER ask you to do work ‘in your head’ – that’s why you’re given a note pad and marker to work with.

4. Now, review each question that you spent 3+ minutes on. How many of those questions had ‘insufficient’ notes attached to them? By extension, how hard would it have been to write down those notes?

5. Try redoing each question, from scratch. Write down all of the notes (as defined above). How long did it take to JUST write down the notes? Not too long, I bet. Now, try to solve the problem. If you decide it’s too hard, then that’s fine… now dump it (take a guess and move on). Physically do it. Choose an answer. Accept that making that choice is in your best interests– there are questions at the end of the section that you almost certainly CAN correctly answer if you have enough time.

With this newfound perspective, you can start making changes to how you work through practice questions and how you take your CATs. Next time, we’ll talk though how to apply similar ideas to how you handle the Verbal section.

GMAT assassins aren’t born, they’re made, Rich

If you have any questions about anything in this thread, then you can feel free to contact me directly via email or PM.
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