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 Z_c is computed using Z table shown below as

Z_0.005 =1.65, Marging of error, E=4 and standard deviation;=25.

orchestra answered 1 year ago

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