# Sampling populations give 95% confidence intervals

Please give answers with steps.

1) 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.

2) 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?

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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 ...

#### Solution Summary

The expert examines sampling populations which give 95% confidence intervals. An approximate sampling is determined.