Really struggling on Data Sufficiency

Question

I'm doing reasonably well on regular problems, but i'm getting absolutely destroyed on DS questions. My first GMAT club test for quant was a 43, followed by a 32! On the latter exam I got nothing but 700+ questions, lot of them algebra DS types, where I had to plug in numbers, test cases, etc. That is my biggest area of weakness. Any advice on how I can get better on DS?

Thanks.

Thanks.

BrushMyQuant · Answer

Hi,

I will suggest you to solve the problem rather than plugging in numbers. Plugin numbers only when you are not able to solve.
Find out the type of Questions in algebra you are getting wrong. And start working on them.
I don't know how to give a generic advice on this. If you can list down some problems in which you are having issue then probably I can help you out in a better way.

premnath · Answer

DS questions are really troublesome if fundamentals are not clear. In fact most of the time you can solve a problem of numbers, but in DS you may fail.
Because in DS you're expected to get the solution keeping in mind all possibilities.
For example, in number system related question you need to see that conditions hold for all the defined number ranges.
If the question do not mentioned the number range, then the condition must hold true for -ve, +ve , 0, fractions. Hence, checking all these conditions becomes a bit problematic.

However, positive side is when you see the solution of such question you'll definitely learn some fundamentals, which are the basis of solving such problems. So, rather than keying in random numbers in DS question, try to follow the fundamentals method. 
Practice as many DS question as you can, and learn the fundamentals from each wrong answers.

You can practice some of DS questions in the following LINK:

https://questionbank.4gmat.com/mba_prep_sample_questions/data_sufficiency/

KarishmaB · Answer

A few things:

1. The concepts tested on DS questions are exactly the same as the concepts tested on PS questions. If you are doing well on PS questions, there is certainly lots of scope to do well in DS.
2. It is easier to do PS questions since you know there is a unique answer. If you are majorly into number plugging, PS would work. On the other hand, DS will be too time consuming. If you work conceptually, it will not matter whether the question is PS or DS. Plug in numbers/test cases are ineffective approaches for DS questions (except in a few cases). You might want to revisit your concepts since 50% of the Quant section will be DS. e.g. while solving a mod question, putting in values to check will be terrible. Instead find out the range that works. 
3. If you do end up using number plugging, you should put in numbers smartly i.e. you should cover the following ranges x 1 with special attention to x = -1/0/1
4. DS questions test your understanding of the sufficiency condition.

Really struggling on Data Sufficiency

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