The best way to mitigate a low GPA is to build up an alternative transcript. Having said that, I think it'll be worthwhile for you to take a couple of business classes (and get A's) to show that you can handle the classwork. One good thing is that you've been out of college for a while now, so GPA will not be as big an issue as someone who's fresh out of college. Your GMAT will definitely make up a portion of the slack.
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