If you run out of time, any question you haven't answered automatically results in a three percentile point reduction (per question) for that section. So you'll get a score but it may be a very poor score, depending upon how many questions you didn't answer.
The penalty for getting a question wrong is not as high as the one for leaving a question blank - so NEVER leave anything blank. If you have to, pick random answers for any remaining questions. (Note: the penalty can still be pretty severe for a string of wrong answers in a row - if you get 5 or more wrong in a row, the per-question penalty averages about 2 to 2.5 percentile points per question. So this is a better scenario than leaving things blank, but still not a good scenario!)
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Stacey Koprince
GMAT Instructor
Director of Online Community
Manhattan GMAT
Contributor to Beat The GMAT!
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