Question

The values listed below are waiting times​ (in minutes) of customers at two different banks. At Bank​ A, customers enter a single waiting line that feeds three teller windows. At Bank​ B, customers may enter any one of three different lines that have formed at three teller windows. Answer the following questions.

Bank A 6.5 6.6 6.7 6.8 7.1 7.2 7.5 7.7 7.7 7.7 Bank Upper

B 4.2 5.3 5.7 6.3 6.6 7.7 7.7 8.5 9.3 10.0 . Click the icon to view the table of​ Chi-Square critical values. Construct a 99​% confidence interval for the population standard deviation sigma at Bank A. 0.30 minless thansigma Subscript Bank Upper Aless than 1.09 min ​(Round to two decimal places as​ needed.)

Construct a 99​% confidence interval for the population standard deviation sigma at Bank B.

Answer 1

The software output for this problem is:

Hence,

99% confidence interval will be:

1.14 < sigma < 4.19