Solve the following:
Q1) The accounting firm of Ahmadi & Associates was commissioned to audit a population of 500 accounts. For this audit, Ahmadi & Associates selected a simple random sample of 64 accounts. The sample showed a mean discrepancy of $120 with a standard deviation of $24. Develop an approximate 95% confidence interval for the population total discrepancy.
Q2) We are interested in selecting a sample from a population of size 4000 in order to develop an approximate 95% confidence interval estimate of the population mean. A pilot study has resulted in a standard deviation of 600. What should be the sample size if we do not want the sampling error to exceed 200?