Question

S6.6 Sampling four pieces of precision cut wire( to be used in computer assembly) every hour for past 24 hours has produced the following results:

hour	xbar	R	HOUR	XBAR	R
1	3.25CM	0.71CM	13	3.11CM	0.85CM
2	3.10	1.18	14	2.83	1.31
3	3.22	1.43	15	3.12	1.06
4	3.39	1.26	16	2.84	0.50
5	3.07	1.17	17	2.86	1.43
6	2.86	0.32	18	2.74	1.29
7	3.05	0.53	19	3.41	1.61
8	2.65	1.13	20	2.89	1.09
9	3.02	0.71	21	2.65	1.08
10	2.85	1.33	22	3.28	0.46
11	2.83	1.17	23	2.94	1.58
12	2.97	0.40	24	2.64	0.97

Develop appropriate control charts and determine whether there is any cause for concern in the cutting process. Plot the information and look for patterns.

Answer 1