A Major Department Store Chain Is Interested in Estimating the Mean

Multiple Choice

A major department store chain is interested in estimating the mean amount its credit card customers spent on their first visit to the chain's new store in the mall.Fifteen credit card accounts wererandomly sampled and analyzed with the following results: $\bar { X } = \$ 50.50$ and S = 20 , S being thestandard deviation.Construct a 95% confidence interval for the mean amount its credit card customers spent on their first visit to the chain's new store in the mall if the amount spent follows a normal distribution.

A) $50.50 $\pm$ $9.09
B) $50.50 $\pm$ $10.12
C) $50.50 $\pm$ $11.00
D) $50.50 $\pm$ $11.08