Back Shoulder Sports manufacturers collegiate footballs. Each day the company verifies the accuracy of the manufacturing process by taking a random sample of 250 footballs. The footballs are either labeled as acceptable or defective. The table below contains historical data of inspected samples taken when the manufacturing process was in control.
|
Sample Number
|
Sample Size
|
Footballs with Defects
|
|
1
|
250
|
7
|
|
2
|
250
|
5
|
|
3
|
250
|
19
|
|
4
|
250
|
10
|
|
5
|
250
|
11
|
|
6
|
250
|
8
|
|
7
|
250
|
12
|
|
8
|
250
|
9
|
|
9
|
250
|
13
|
|
10
|
250
|
18
|
|
11
|
250
|
5
|
|
12
|
250
|
16
|
|
13
|
250
|
4
|
|
14
|
250
|
11
|
|
15
|
250
|
6
|
a) Construct the appropriate control chart from the above data using a 3-standard deviation limit.