Mr. price Home analyzed the value of purchase made on credit by a sample of 25 credit card customers. The simple mean was found to be R170.08 with a sample standard deviation of R21.90. Assume purchase values are normally distributed.
1. Estimate with 95% confidence, the actual mean value of credit card purchases at this store.
2. Assume 46 credit card purchases were sampled. Set 95% confidence limits for the actual mean value of credit purchases at Mr. price Home.