Question 844294
Find the mean and standard error of the sample means that is normally distributed with a mean of 10 and a standard deviation of 2 and a sample size of 25.
mean of the sample means = 10
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std of the sample means = 2/sqrt(25) = 2/5
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using the above distribution find the probability of a score less than 11.
z(11) = (11-10)/0.4 = 1/(4/10) = 5/2 = 2.5
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P(x-bar < 11) = P(z < 2.5) = normalcdf(-100,2.5) = 0.9938
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Cheers,
Stan H.
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