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题库 / Prep2007E2-PS-126
9.4 9.9 9.9 9.9 10.0 10.2 10.2 10.5
The mean and the standard deviation of the 8 numbers shown are 10.0 and 0.3, respectively. What percent of the 8 numbers are within 1 standard deviation of the mean?
90%
85%
80%
75%
70%
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