Hi krishhxa,

The main OG is a great book for practice questions (and most Test Takers use some version of that book during their studies). The subject-specific books can also be useful if you're looking for additional practice question in either the Quant or Verbal. However, any combination of those 3 books will likely NOT be enough study material for you to achieve your goals. They are great sources for practice questions, but they're not designed to teach you the Tactics, patterns or little 'secrets' to the GMAT. As such, you'll likely need a wider array of practice materials.

1) What is your goal score?
2) When are you planning to take the GMAT?
3) Have you done any studying for the GMAT so far?

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

Hi krishhxa,

To start, you might want to pose your questions in the General Strategy Forum here:

https://www.beatthegmat.com/gmat-strategy-f3.html

Given what you've described, you will likely find it difficult to score 750+ with just one month of studying. Many Test Takers spend 3 months (or more) on their studies before they hit their 'peak' scores. Since you have not started yet, we don't even have a sense of your current abilities, strengths and weaknesses.

Since you're just beginning, then it would be a good idea to take a FULL-LENGTH practice CAT Test; you can download 2 for free from www.mba.com (and they come with some additional practice materials). A FULL CAT takes about 4 hours to complete, so make sure that you've set aside enough time to take it in one sitting. Once you have those scores, you should report back here and we can come up with a study plan.

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