A major department store chain is interested in estimating the mean and now it's credit card customers spend on their first visit to the chain's new...

A major department store chain is interested in estimating the mean and now it's credit card customers spend on their first visit to the chain's new store in the mall. Nine Credit card accounts were randomly sampled and analyzed with the following results: X-bar = 50.50, S = 24. Using this information develop a 90% confidence interval for the mean amount it's credit card customer spend on their first visit to the chains new store in the mall.