Data from Wilmer's Machine shop machining process over a 20-hour period is provided in the accompanying Excel workbook. Every half hour, a sample of five items was taken from the manufacturing process and each item in the sample was measured in millimetres. Compute the average and range of each sample group and thereafter calculate the central lines (Mean lines) for both the average and range values. Calculate the upper and lower control limits for both the average values and the range values using the formulas and table in the class notes. Plot a control chart for average as well as a range using the above data and specify whether the process is in statistical control. Motivate your answer as you need to provide feedback and recommendations to the operations manager.

Sample	Observation [mm]						Average	Range
1	3,55	3,64	4,37	3,00	3,71		3,65	1,37
2	3,61	3,42	4,07	4,37	3,51		3,80	0,95
3	3,61	3,36	4,34	4,07	3,00		3,68	1,34
4	4,13	3,50	3,61	4,34	3,20		3,76	1,14
5	4,06	3,28	3,07	3,61	3,43		3,49	0,99
6	4,48	4,32	3,71	3,07	3,55		3,83	1,41
7	3,25	3,58	3,51	3,71	3,61		3,53	0,46
8	4,25	3,38	3,00	3,51	3,61		3,55	1,25
9	4,35	3,64	3,20	3,00	4,13		3,66	1,35
10	3,62	3,61	3,43	3,20	4,06		3,58	0,86
11	3,09	3,28	3,12	3,43	4,48		3,48	1,39
12	3,38	3,15	3,09	4,37	3,25		3,45	1,28
13	2,85	3,44	4,06	4,07	4,25		3,73	1,40
14	3,59	3,61	3,34	4,34	4,35		3,85	1,01
15	3,60	2,83	2,84	3,61	3,62		3,30	0,79
16	2,69	3,57	3,28	3,07	3,09		3,14	0,88
17	3,07	3,18	3,11	3,71	3,38		3,29	0,64
18	2,86	3,69	3,05	3,51	2,85		3,19	0,84
19	3,68	3,59	2,82	3,00	3,59		3,34	0,86
20	2,90	3,41	3,37	3,20	3,60		3,30	0,70
21	3,57	3,63	2,72	3,43	2,69		3,21	0,94
22	2,82	3,55	3,56	3,12	3,07		3,22	0,74
23	3,82	2,91	3,80	3,09	2,86		3,30	0,96
24	3,14	3,83	3,80	4,06	3,68		3,70	0,92
25	3,97	3,34	3,65	3,34	2,90		3,44	1,07
26	3,77	3,60	3,81	2,84	3,57		3,52	0,97
27	4,12	3,38	3,37	3,28	2,82		3,39	1,30
28	3,92	3,60	3,54	3,11	3,82		3,60	0,81
29	3,50	4,08	4,09	3,05	3,14		3,57	1,04
30	4,23	3,62	3,00	3,93	3,97		3,75	1,23
31	4,37	3,62	4,37	3,37	3,77		3,90	1,00
32	4,07	3,09	4,07	2,72	4,12		3,61	1,40
33	4,34	3,38	4,34	3,56	3,92		3,91	0,96
34	3,61	2,85	3,61	3,80	3,50		3,47	0,95
35	3,07	3,59	3,07	3,80	4,23		3,55	1,16
36	3,71	3,60	3,71	3,65	4,37		3,81	0,77
37	3,51	2,69	3,51	3,81	4,07		3,52	1,38
38	3,00	3,07	3,00	3,37	4,34		3,36	1,34
39	3,20	2,86	3,20	3,54	3,61		3,28	0,75
40	3,43	3,68	3,43	4,09	3,07		3,54	1,02