A statistician selected a sample of 16 accounts receivable and determined the mean of the sample to be $5, 000 with a standard deviation of $400 . He...

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A statistician selected a sample of 16 accounts receivable and determined themean of the sample to be $5, 000 with a standard deviation of $400 . He reportedthat the sample information indicated the mean of the population ranges from$4 , 739.80 to $5, 260. 20 . He neglected to report what confidence coefficient hehad used . Based on the above information , determine the confidence coefficientthat was used . Assume the population has a normal distribution .Answer :!0 . 98A researcher is interested in determining the average number of years employeesof a company stay with the company . If past information shows a standarddeviation of 7 months , what size sample should be taken so that at 95 %confidence the margin of error will be 2 months or less ?"Answer :"48