Question

The annual earnings of 14 randomly selected computer software engineers have a sample standard deviation of $3668. Assume the sample is from a normally distributed population. Construct a confidence interval for the population variance sigma squared σ2 and the population standard deviation σ. Use a 95% level of confidence. Interpret the results.

1. What is the confidence interval for the population variance σ2​?

(____,___)

2. Interpret the results. Select the correct choice below and fill in the answer​ box(es) to complete your choice.

​(Round to the nearest integer as​ needed.)

A. With 5​% confidence, you can say that the population variance is between ___ and ___.

B. With 95% confidence, you can say that the population variance is greater than ____.

C. With 95 % confidence, you can say that the population variance is between ____ and ___

D. With 5​% confidence, you can say that the population variance is less than ____.

3. What is the confidence interval for the population standard deviation σ​?

(___,___)

4. Interpret the results. Select the correct choice below and fill in the answer​ box(es) to complete your choice.

A. With 5​% confidence, you can say that the population standard deviation is between ​$___and $___.

B. With 95​% ​confidence, you can say that the population standard deviation is between ​$___and $___ .

C. With 5​% confidence, you can say that the population standard deviation is greater than ​$____.

D. With 95​% ​confidence, you can say that the population standard deviation is less than ​$___.

Answer 1