Recent GMAT Questions from the GMATprep CD.

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by gmatblood » Tue Nov 01, 2011 10:23 am
imo: 11

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by GmatMathPro » Tue Nov 01, 2011 10:25 am
Standard deviation is 0.3, so 1.5 standard deviations would be 0.3*1.5=0.45, so we want all data points that are between the 8.1+-0.45. That is, between 7.65 and 8.55. Only 7.51 is outside of this range, so 11 is the answer.
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