Question

Please assist with the information below.

Use the Table below for questions 20-22. The data describes customer waiting times at Marcia Italian Restaurant.

Day	Supbroup size	Subgroup Mean	Subgroup Range
1	5	2.4	3.35
2	5	2.94	4.98
3	5	3.68	3.46
4	5	2.78	4.27
5	5	3.99	4.32
6	5	3.6	4.84
7	5	2.89	3.97
8	5	1.86	3.81
9	5	3.43	3.48
10	5	2.34	3.24

What is the D4 value from Control Chart Factor table for this subgroup size?

1. 0
2. 1.777
3. 2.114
4. Not computable

21. Is the variation of this process under control?

1. The mean of this process is not important
2. The variation of this process appears in control
3. Need to check if mean of the process is under control first
4. More data is required to make any assessment

22. Is the mean of the process under control?

1. The mean of the process is never relevant
2. Does not matter since the variation of the process is out of control
3. The mean of the process appears in control
4. No, the mean of the process does not appear in control

Answer 1