The following samples have been taken from an on-going process. Use these values
ID: 3363912 • Letter: T
Question
The following samples have been taken from an on-going process. Use these values to create both an X bar and an R chart, and then answer the questions below.
Sample 1: 56 48 53 58 52
Sample 2: 50 59 57 58 54
Sample 3: 61 57 56 55 58
Sample 4: 57 51 47 57 50
Sample 5: 49 49 57 55 56
Sample 6: 56 55 60 58 58
1)What is the value of the centerline for an X bar chart? (Round to two decimal places)
2)The upper control limit for the X bar chart is:
3)The lower control limit for the X bar chart is:
4)The upper control limit for the R chart is:
5)The lower control limit for the R chart is:
Explanation / Answer
The statistical software output for this problem is:
Control chart results:
Xbar Chart results:
Upper control limit = 59.4402
Center line = 54.9
Lower control limit = 50.3598
R Chart results:
Upper control limit = 18.8376
Center line = 9.4
Lower control limit = 0
Hence,
1) Centerline for an X bar chart = 54.9
2)The upper control limit for the X bar chart = 59.44
3)The lower control limit for the X bar chart = 50.36
4)The upper control limit for the R chart = 18.84
5)The lower control limit for the R chart = 0