Question

As part of a​ survey, a marketing representative asks a random sample of 29 business owners how much they would be willing to pay for a website for their company. She finds that the sample standard deviation is ​$3433. Assume the sample is taken from a normally distributed population. Construct 99​% confidence intervals for​ (a) the population variance sigma squared and​ (b) the population standard deviation sigma. Interpret the results. (a) find the confidence interval for population variance (b)Interpret the results. Select the correct choice below and fill in the answer​ box(es) to complete your choice. ​(Round to the nearest integer as​ needed.) A. With 1​% ​confidence, you can say that the population variance is less than nothing. B. With 99​% ​confidence, you can say that the population variance is between nothing and nothing. C. With 1​% ​confidence, you can say that the population variance is between (nothing and nothing). D. With 99​% ​confidence, you can say that the population variance is greater than (nothing). ​(b) The confidence interval for the population standard deviation is ​( nothing​, nothing​). ​(Round to the nearest integer as​ needed.) Interpret the results. Select the correct choice below and fill in the answer​ box(es) to complete your choice. ​(Round to the nearest integer as​ needed.) A. With 99​% ​confidence, you can say that the population standard deviation is between ​$ (nothing and ​$ nothing). B. With 99​% ​confidence, you can say that the population standard deviation is less than ​$ (nothing). C. With 1​% ​confidence, you can say that the population standard deviation is greater than ​$ (nothing). D. With 1​% ​confidence, you can say that the population standard deviation is between ​$ (nothing and ​$ nothing).

Answer 1

(a)

n = 29

s= 3433

= 0.01

ndf = 29 - 1 = 28

99% Confidence Interval:

Low End:

From Table:

So,

Low End :

High End:
From Table:

So,

High End:

So,

Confidence interval:

6471277 < < 26481482

Correct option:

B. With 99% Confidence, you can say that the population variance is between 6471277 and 26481482.

(b)

99 % confidence interval:

Low End:

High End:

99% Confidence interval:

2544 < < 5146

Correct option:

A. With 99% confidence, you can say that the population standard deviation is between 2544 and 5146.