Need some Quant crash-course last min advice :-)

Hi Abhi, I second Akhilesh here. You are doing great at Quant but its good to see that you are not taking it lightly (you don't want to make any crazy mistakes and get a 49 instead of 51). A few pointers from me:

- perhaps good to review some posts from Bunuel on areas that you are taking longer to solve (you can also access these via GMAT Club Math Book project page)
- from OG 12, perhaps do the last 50 questions for PS and DS.
- also from what I have heard it will be good to do the 150 problems in Adv Quant book from MGMAT.
- once again, Akhilesh's last comment is extremely important to remember: if you get stuck on problem for more than 2.5-3min, guess and move do not try to take the problem head on. If you take it head on and spend more than 5 mins on it, this will unnecessary play on your mind for the rest of quant section. You really don't want that.

Good luck!

There is no known weakness, at least not i could perceive. Sometimes i get 1-2 number prop wrong, sometimes 1-2 word translations - it's totally random though; mostly silly due to some assumption. I have never got any geomatry or comb/prob wrong in any teat thus far. Earlier on I realized that equalities was something I would spend a lot of time, so I kind of developed few strategies of my own, and since then I don't face too many problem. Also early on I would a lot of time on overlapping sets, but I have developed a strategy of my own and it has been workig great for me.

Regarding the GMAT Club tests, I feel like some questions are worded way too vague for GMAT standards and in-general. I have lost interest in it. My performance there has varied - out of 5-6 (i think) that i have given, sometimes I get very few wrong and sometimes many wrong - buy lostly because I get disinterested in the middle of the test and want to wrap it ASAP. Do you really think those tests as helpful? Frankly, I find them a little bit vaguely wordly. Maybe it is just me.

Posted from GMAT ToolKit

Thanks Vinay and Akhilesh,

I think will get that Advanced Strategy book and practice some from there, and see if I get of the short-cuts.

Thing is, since I have never never ram out of time, I feel more comfortable just to solve it till eternity as I know I will gain time in other questions. Now I am starting to realize I should put a cap of 3 mins to solve any problem and if I have not gotten an ans, I will try to find an ans in next 30 secs. Although I have always finished all the quant tests before time, but again without any dedicated effort to understand the time I might be in trouble on the final day. You guys are right that I should start having that small but imp strategy in place. I will keep a note in my coming tests. Thanks.

Posted from GMAT ToolKit

hi Abhi, can you please share your strategies for Inequality & Overlapping sets? I face some issues in both these areas and will be thankful for any help. Thanks.

You know what - we both are in exactly the same situation.
I too feel exactly the same about gmatclub tests - too vaguely worded, sometimes typos and too less information to solve the sum. But I am finishing them just to improve on silly mistakes I make and I have a lot of prep time left!

And in Quant I have yet to run out of time - I take as many as 3.5 minutes to solve some questions and sometimes a difficult question can be solved in under 30 secs!
So timing is not an issue. But remember GMATPrep questions are much different. The beautiful thing about GMAT Quant questions is that every question is uniform! So timing may become an issue!

MGMAT Does a pretty good job at explaining inequalities & overlapping sets! Do you have their guide?

Yes, I have those guides and am used to the usual technique for solving them but I think Abhi here will have some more & better insights on approaching these questions

For inequalities, having a "feel" of numbers is the key. As soon as I see an inequality ANYWHERE in a question, my mind automatically draws that equation in the cartesian coordinates, and if it involves 3 variables then in 3D. Most often than not I can solve many problems just by imagining those numbers in the plan or 3D. Knowledge of how to imagine rectangle/cube, circle/sphere, parabola, etc helps, at-least for me. If needed I use notebook for questions involving multiple equations. I have never tried substitution as I don't want solve using random number and rather I want to get a feel of these numbers. GMAT problems are simple enough to represent in 2D, or very rarely 3D, and could be solved without writing many complex equations - sometimes of-course you do. But the point is instead of crunching some random number by substitution, I personally like get a feel of those numbers. If you can give me problem that you found most challenging, I will try my best to illustrate how this works but I hope I was able to convey my "personal" idea at high level.

If you are always getting 700-800 level questions, then you can't imagine GMAT to give to straightforward overlapping sets. It's all about ratio in Overlapping Sets. One crude way to solve is to use one of the standard 3 column-3 row strategy (I am sure GMAT books document it with some other name, I don't know) - for 2 overlapping sets, each with 2 mutually exclusive events. However, it can become tricky if you have > 2 sets and > 2 mutually exclusive events per set - the only way to solve these advanced problems is to use Venn Diagram. I always "try" to draw these Venn Diagrams to the same aspect ratio as give in the question. Venn Diagrams give you the feel. I don't memorize any formula as GMAT problems is tricky enough to make those formula confusing. Again I try to get a "feel" of the data given to me.

Hope this helps Sorry, if this doesn't work for you, as these are some things my mind likes to do when it sees these numbers so I can't say it will work for all.

GMATClub tests make be disinterested in quant and I don't to have that feeling. A good quant problem will not need you to make any assumption - in GMAT Club tests you sometimes need to know how few things work in real life, which is not how GMAT problems look.

I bought the MGMAT Advance Strategy book. I will spend 1 full day next weekend and finish that book - hope I get something good out of it.

In addition, in-case you find all or some of the above too abstract please ignore, BUT I would HIGHLY recommend using number line to solve inequality problems involving just 1 variable.

Eg. for x^2 < 4 = quickly draw a line (X-axis) around origin and mark everything b/w -2 and 2, excluding 2. In addition, if you have more inequalities keep using the same number line or just a line parallel to that X-axis. This makes the problem so much easier. If you keep dealing in number you might take longer for tricky problems. Anyways, just my 2 cents as these are the most common ones in GMAT.

The issue you keep describing is called "brute force solving". I had the same issue during the GMAT.

The solution is make sure you are answering ONLY what the problem is asking. The more you dive into a problem solving unnecessary things, the more you stress/burn out. Make sure you are answering the question asked and nothing more.

Thanks Abhi for these tips! They are quite helpful.

For Inequalities - I figured out that its best to use number line (as you said esp. for single variable questions) and pay specific attention to the boundaries for the solution. So, thanks for reinforcing that it is preferred method for you too. I have tried using Cartesian approach to do inequalities but for me that takes longer sometimes - although the assurance that you have reached the correct answer is higher when using cartesian approach.

For overlapping sets - I brushed my basics and now I use dual approach sometimes tables (2X2) and sometimes venn diagram. I need to still get a hang of some specific problem types. I agree that formulas have landed me in trouble in these questions. Thanks again!