Question

In: Statistics and Probability

A large Midwestern university is interested in estimating the mean time that students spend at the...

A large Midwestern university is interested in estimating the mean time that students spend at the student recreation center per week. A previous study indicated that the standard deviation in time is about 25 minutes per week. If the officials wish to estimate the mean time within ± 4 minutes with a 90 percent confidence, what should the sample size be?

106

Can't be determined without the sample mean.

105

105.685

Solutions

Expert Solution

The Minimum sample is calculated as

where Zc is computed using Z table shown below as

Z0.005 =1.65, Marging of error, E=4 and standard deviation;=25.

orchestra answered 2 years ago
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