Shrinidhi wrote:

Hello David,

Can you Just suggest me upon how to prepare for DS from scratch?And resources which would prove to be helpful. Everything I need to do for acing the DS section.

Posted from my mobile device

Hello

Shrinidhi,

Thanks for the question!

First off, we made a video on exactly that topic, see it

hereIn words, the first thing you need to do is realize that there is a very large difference between 'regular multiple choice' PS questions and DS questions.

In PS, you are asked a question and need to calculate the answer to the question.

In DS, you only need to figure out if a certain statement gives you enough information so that you could potentially calculate the answer should you really want to.

For example, if a PS question were to ask you "3^10 = ?" you would actually need to calculate 3 to the power of 10 and look for the relevant answer choice.

If a DS question were to ask you "x^10 = ?" then all you would need to do is look for a statement that tells you the value of x (which would then let you calculate x^10, if you really wanted to).

So "x = 3" would be sufficient as would be "2x + 5 = 11" as would be "x^3 = 27". Each of these allows us to calculate the value of x, which then allows us to calculate the value of x^10. Note that we didn't actually have to complete the calculations! All we had to do was realize that the above statements allow us to calculate the answer, should we want to. This focus on 'sufficiency' and not on 'actually calculating' is the most important thing to realize when going into DS. Once you've got this down, your life becomes much easier and your scores much higher.

The answer choices also reflect this 'information-focus':

Select (A) when the first statement on its own gives you enough information, and the second does not

Select (B) when that the second statement on its own is enough, and the first is not

Select (C) when you must combine both statements to have enough information

Select (D) when each of the statements on its own gives enough information

Select (E) when, even when you combine both statements together, you still don't have enough information

Other than that, much of the routine 'learning the material' work is the same. You need to know the concepts behind, for example, number properties, rate and work, powers and roots, linear equations and so on... You need to learn common GMAT traps, such as missing a negative option or forgetting about zero.

In particular, you need to develop

cognitive flexibility - the ability to choose the right tool for the right question. Is it better to just count the number of variables and equations and see if you have enough equations to solve (a Logical approach)? Should you maybe try out a few numbers to help make things concrete (an Alternative approach)? Maybe just dive straight into algebra and simplify (a Precise approach)?

Additionally, you need to

learn from your mistakes. Did you miss a negative or positive option? Did you get confused with prime factoring? Every mistake you make should be listed in an error log and you should try 'fixing' your mistake before moving on to the next question. You can either build up this

error log on your own or you can let someone else do it for you. On our platform, we use an AI to choose, based on each individual student's preferred solution tools and common mistake reasons, the set of questions and solution approaches that are best for them. If you like,

give us a go.

If you're having difficulty with a specific question and would like my input on it, please don't hesitate to ask!

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