Hi
JayashreeSudhakar,
As many have already mentioned, there isn't a specific number of correct questions to guarantee an 85th percentile score in all three sections of the GMAT. This is because the GMAT adapts to your performance, so the difficulty of the questions (in addition to the quantity) you get wrong affects your section scores.
More importantly, fixating on the "exact number" of questions you can get wrong for a specific score won't be very helpful on test day. Sometimes, you get a question wrong without realizing it or get questions right through lucky guesses. So it's impossible, with 100 percent certainty, to keep track of how many questions you've answered correctly in a particular section.
So, the best thing you can do moving forward is focus on preparing as best as you can and doing your best on test day.
If you have any more questions, feel free to reach out.