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Difference in variability and P value

Sample Question:
A bank a branch location a commercial district we city developed improved process serving customers noon-to 1 pm. lunch period. the waiting time (defined as the time elapsed from when the customer enters the line until he or she reaches the teller window) needs to be shortened to increase customer satisfaction. A random sample of 15 customers is selected (and stored in Bank 1), and the results (in munities) are as follows:
4.21 5.55 3.02 5.13 4.77 2.34 3.54
4.5 6.1 0.38 5.12 6.46 6.19 3.79

Suppose that another branch, located in a residential area, is also concerned with the noon-to1 pm. Lunch period A random sample of 15 customers is selected (and stored in Bank 2), and the results (in minutes) are as follows:
9.66 5.9 8.02 5.79 8.73 3.82 8.01 8.35
10.49 6.68 5.64 4.08 6.17 9.91 5.47

A. Is there evidence of a difference in the variability of the waiting time between the two branches?
(use a=0.05)

B. Determine the P value in (a) and interpret its meaning

C. What assumption about the population distribution of the two banks is necessary in
(a)? Is the assumption valid for these data?

D. Based on the results of (a) is it appropriate to use the pooled-variance
t-test to compare the means of the two branches?

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Hi need help to understand this question, thanks please show in excel format, I am visual person
Sample Question:
A bank a branch location a commercial district we city developed improved process serving customers noon-to 1 pm. lunch period. the waiting time (defined as the time elapsed from when the customer enters the line until he or she reaches the teller window) needs to be shortened to increase customer satisfaction. A random sample of 15 customers is selected (and stored in Bank 1), and the results (in munities) are as follows:
4.21 5.55 3.02 5.13 4.77 2.34 3.54 3.20 (you forgot to list observation #8 from the Bank1 dataset)
4.5 6.1 0.38 5.12 6.46 6.19 3.79

Suppose that another branch, located in a residential area, is also concerned with the noon-to1 pm. Lunch period A random sample of 15 customers is selected (and stored in Bank 2), and the results (in minutes) are as follows:
9.66 5.9 8.02 5.79 8.73 3.82 8.01 8.35
10.49 6.68 5.64 4.08 6.17 9.91 5.47

A. Is there evidence of a difference in the variability of the waiting time between the two branches?
(use a=0.05)
This question suggests the ...

Solution Summary

The difference in variability and P values are examined.

$2.19