Hello, Suhassrivats! Our psychometric team saw your question and has passed along this answer:

For the 25,800 calendar year 2011 test takers scoring 700 and above, the mean (and standard deviation) of the number of correct answers were 31.6 (3.6) and 29.9 (4.0) for Verbal and Quant, respectively. The minimums were 19 and 17 respectively. Please keep in mind that the GMAT is an adaptive test and scoring is based on the item difficulties and the responses to all the questions that were administered. Testing starts with questions that are about average difficulty. The test taker would probably have a string of mostly right answers before being administered questions that are well matched to his or her ability and have a 50% chance of being correct. Also imbedded in the test are randomly administered research questions that do not contribute toward total score.