Take a look here - this scenario has been repeated and experimented with many times by those of us who could not imagine anything more entertaining than taking a GMAT Prep test: gmat-prep-software-analysis-and-what-if-scenarios-146146.html
P.S. The quick answer is - not big
2. What is the importance of the last 10 questions?
Experiment: We will try to analyze the importance of the last 10 questions and if it equals the important of the first 10
Methodology: we will attempt the worst case scenario and will answer the first 27 Q questions correctly and then will answer the remaining 10 questions incorrectly (not guess but incorrectly).
Results: Q50, 92nd percentile - Nicely done though not great. I think it is possible to get Q51 with 10 incorrect ones.
Analysis: The questions were much harder this time with some new topics/types appearing on the test such as coordinate geometry DS. Conclusion: the last 10 don't count as much as the first 10. This myth is True (as long as you can get the first 27 right). Please note that I have not guessed the last 10 but rather answered them incorrectly (which means I still had to solve those questions too). If you are guessing, you will most likely get a higher score.
Total Score: every question in the verbal section was answered as "E" (again) and it resulted in the final score of V8, 1st percentile. Total score: 470 (90 points higher than when we missed the first 10 questions)
Questions: 20PS and 17 DS. Also, see what question topics were encountered in this scenario:
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