The Graduate Management Admission Test (GMAT) has scores from 200 to 800.
Scores are supposed to follow a distribution that is roughly unimodal and symmetric
and is designed to have an overall mean of 500 and a standard deviation of 100. In any
one year, the mean and standard deviation may differ from these target values by a
small amount, but we can use these values as good overall approximations.

QUESTION: 

Suppose you earned a 600 on your GMAT. From that information and
the 68-95-99.7 Rule, where do you stand among all students who took the GMAT?