Statistics
posted by Kristi .
Please help!! I have no idea how to do this question.
14. A sample of 40 CD’s from your collection showed a mean length of 52.74 minutes with a standard deviation of 13.21 minutes
a. Construct the 95 percent confidence interval for the mean.
b. Construct the 95 percent confidence interval for the mean using the tvalue rather than the zvalue. Comment on why the interval is larger when you use the tvalue.
c. Why might normality of the data set be in question here? Comment on your answer.
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