Chapter 16, Problem 43SE

The following numbers are observations on tensile strength of synthetic fabric specimens selected from a production process at equally spaced time intervals. Construct appropriate control charts, and comment (assume an assignable cause is identifiable for any out-of- control observations).

1	51.3	51.7	49.5
2	51	50	49.3
3	50.8	51.1	49
4	50.6	51.1	49
5	49.6	50.5	50.9
6	51.3	52	50.3
7	49.7	50.5	50.3
8	51.8	50.3	50
9	48.6	50.5	50.7
10	49.6	49.8	50.5
11	49.9	50.7	49.8
12	49.6	48.4	50
13	49.8	51.2	49.7
14	50.4	49.9	50.7
15	49.4	49.5	49
16	50.7	49	50
17	50.8	49.5	50.9
18	48.5	50.3	49.3
19	49.6	50.6	49.4
20	50.9	49.4	49.7
21	54.1	49.8	48.5
22	50.2	49.6	51.5