. Ms. St. John would like to estimate the average number of minutes that Connections Cellular’s customers spend on out-of-network calls per month. She requests that the estimate use the 99 percent confidence level with a margin of error of no more than five minutes.

a. A previous study indicated that the standard deviation for out-of-network calls is 21 minutes per month. What should the sample size be?

b. Determine the required sample size if you changed the confidence level from 99 percent to 95 percent.

c. What would the required sample size be if the confidence level w

Question

. Ms. St. John would like to estimate the average number of minutes that Connections Cellular’s customers spend on out-of-network calls per month. She requests that the estimate use the 99 percent confidence level with a margin of error of no more than five minutes.

a. A previous study indicated that the standard deviation for out-of-network calls is 21 minutes per month. What should the sample size be?




b. Determine the required sample size if you changed the confidence level from 99 percent to 95 percent.




c. What would the required sample size be if the confidence level w