Thanks for posting. Regarding your GMAT score, if you believe you can improve your score I recommend you take the test again. The reason is because although your score is only 50 points lower than the average of the schools you are looking at, it does put you in a low percentile.
Understand that your GMAT score is self-reported on your business school application, so admissions teams will only focus on your highest score. There isn't a downside to taking the test again (other than the cost and the time spent studying).
Regarding your undergraduate GPA, I recommend you read this case study of a candidate with a sub 3.0 GPA who was accepted into both Columbia and Chicago Booth:http://www.stacyblackman.com/comprehens ... ies/case5/
Hope this was of help.
Conrad and the Stacy Blackman
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