Chapter 10, Problem 2.1CQ

Summary Introduction

To determine: The rationale behind JM concluding that first set of sample was not capable.

Introduction

Company TT is a division of company DM. It was about to launch a new product. Ms. MY, the production manager, asked her assistant JM to check the capability of the oven. JM collected 18 random samples from each of the 20 pieces. After the analysis, the samples proved to be incapable based on the specification width of 1.44 cm.

Table 1

Sample	Mean	Range
1	45.01	0.85
2	44.99	0.89
3	45.02	0.86
4	45	0.91
5	45.04	0.87
6	44.98	0.9
7	44.91	0.86
8	45.04	0.89
9	45	0.85
10	44.97	0.91
11	45.11	0.84
12	44.96	0.87
13	45	0.86
14	44.92	0.89
15	45.06	0.87
16	44.94	0.86
17	45	0.85
18	45.03	0.88

Quiet disappointed with the end results, the manager was figuring out ways to improve the process and free the capital expenditure of $10,000. A former professor suggested going for more samples with less sample sizes. JM conducted the analysis on27 samples of 5 observations each and the results are tabulated below:

Table 2

Sample	Mean	Range
1	44.96	0.42
2	44.98	0.39
3	44.96	0.41
4	44.97	0.37
5	45.02	0.39
6	45.03	0.4
7	45.04	0.39
8	45.02	0.42
9	45.08	0.38
10	45.12	0.4
11	45.07	0.41
12	45.02	0.38
13	45.01	0.41
14	44.98	0.4
15	45	0.39
16	44.95	0.41
17	44.94	0.43
18	44.94	0.4
19	44.87	0.38
20	44.95	0.41
21	44.93	0.39
22	44.96	0.41
23	44.99	0.4
24	45	0.44
25	45.03	0.42
26	45.04	0.38
27	45.03	0.4