A new manufacturer of light bulbs attempting to penetrate the market wants to assess its process for producing the bulbs. It is concerned about the number of defective bulbs found recently.
In order to evaluate the true magnitude of the problem, a production manager selected ten random samples of 20 units each for inspection.
The number of defective bulbs found in each sample are as follows:
|
Sample
|
Sample Size(n)
|
Number Defective
|
|
1
|
20
|
1
|
|
2
|
20
|
3
|
|
3
|
20
|
2
|
|
4
|
20
|
1
|
|
5
|
20
|
4
|
|
6
|
20
|
1
|
|
7
|
20
|
2
|
|
8
|
20
|
0
|
|
9
|
20
|
3
|
|
10
|
20
|
1
|
PLEASE SOLVE A and B
A. Using this data, develop a 3s p-chart (i.e., Z = 3.00). Determine the centerline, UCL and LCL. What conclusion can you make?
B. After creating the p-chart with the original ten sample data measures, suppose the next four samples selected, each with 20 observations, had 6, 3, 3, and 4 defects. What conclusion would these four samples lead you to make?