Question

Assume that the sample is a simple random sample obtained from a normally distributed population of IQ scores of statistics professors. Use the table below to find the minimum sample size needed to be 95 ​% confident that the sample standard deviation s is within 30 ​% of sigma . Is this sample size​ practical? sigma To be​ 95% confident that s is within ​1% ​5% ​10% ​20% ​30% ​40% ​50% of the value of sigma ​, the sample size n should be at least ​19,205 768 192 48 21 12 8 To be​ 99% confident that s is within ​1% ​5% ​10% ​20% ​30% ​40% ​50% of the value of sigma ​, the sample size n should be at least ​33,218 ​1,336 336 85 38 22 14

The minimum sample size needed is ? .

Is this sample size​ practical?

A. Yes ​, because the sample size is small enough to be practical for most applications.

B. ​Yes, because the sample size should be as large as possible for most applications.

C. No ​, because the sample size is excessively large to be practical for most applications.

D. ​No, because the sample size should be as small as possible for most applications.

Answer 1