I know next to nothing about statistics because at my high school it's either calculus or statistics, and I picked calc (no regrets there). I don't have any idea what the mathematical way to identify an outlier would be.
abs(X[i] - mean) > C*sqrt(sum((X - mean(X))^2)) where C is a suitable constant
note this is only one approach and may not work in your case depending on the distribution, if so try some of these: http://en.wikipedia.org/wiki/Outlier...fying_outliers
also, read the AP statistics guide, it should take you a few hours and you'll learn everything you need for the exam
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