At Samantha’s Super Store, the customer service area processes customer returns, answers customer questions and provides
Posted: Wed Jul 06, 2022 6:15 am
At Samantha’s Super Store, the customer service area processescustomer returns, answers customer questions and providesinformation, addresses customer complaints and sells giftcertificates. The manager believes that if customers mustwait longer than 8 minutes to see a customer servicerepresentative, they get very irritated. The customer serviceprocess has been designed to achieve a customer wait time ofbetween 6 and 12 minutes. The store manager has conducted 10samples of 5 observations each of customer waiting time over a twoweek period. The results are shown in the tablebelow.
Sample
Wait Time (min)
Obs 1
Obs 2
Obs 3
Obs 4
Obs 5
Row Sums
1
8.3
9.6
10.2
7.4
3.1
38.6
2
2.8
5.9
6.7
8.3
9.2
32.9
3
11.3
7.4
16.2
20.1
9.5
64.5
4
10.7
7.5
9.8
11.3
4.5
43.8
5
4.3
12.4
10.6
16.7
11.3
55.3
6
5.3
9.7
10.8
11.3
7.4
44.5
7
18.2
12.1
3.6
9.5
14.2
57.6
8
8.1
10.3
8.9
7.2
5.6
40.1
9
9.3
12.4
13.7
7.3
5.2
47.9
10
6.7
8.5
8
10.1
12.3
45.6
Total of
Row Sums
470.8
a) Find the centerline, UCL and LCL for a 3 sigmaX-bar chart for this data
b) Find the centerline, UCL and LCL for an R chartfor this data
c) Is the process in control? Why or whynot?
Sample
Wait Time (min)
Obs 1
Obs 2
Obs 3
Obs 4
Obs 5
Row Sums
1
8.3
9.6
10.2
7.4
3.1
38.6
2
2.8
5.9
6.7
8.3
9.2
32.9
3
11.3
7.4
16.2
20.1
9.5
64.5
4
10.7
7.5
9.8
11.3
4.5
43.8
5
4.3
12.4
10.6
16.7
11.3
55.3
6
5.3
9.7
10.8
11.3
7.4
44.5
7
18.2
12.1
3.6
9.5
14.2
57.6
8
8.1
10.3
8.9
7.2
5.6
40.1
9
9.3
12.4
13.7
7.3
5.2
47.9
10
6.7
8.5
8
10.1
12.3
45.6
Total of
Row Sums
470.8
a) Find the centerline, UCL and LCL for a 3 sigmaX-bar chart for this data
b) Find the centerline, UCL and LCL for an R chartfor this data
c) Is the process in control? Why or whynot?