<PRE><B>Question 682803</B>
A final exam in Statistics has a mean of 73 with a standard deviation of 7.73. Assume that a random sample of 24 students is selected and the mean test score of the sample is computed. What percentage of sample means are less than 70?
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std of the sample means for samples of size 2 is 7.73/sqrt(24) 
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z(70) = (70-73)/[7.73/sqrt(24)] = 1.9013
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P(x &lt; 70) = P(z &lt; 1.9013) = normalcdf(-100,1.9013) = 0.9714
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Cheers,
Stan H.
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