A machine at the Pacific Fruit Company fills boxes with raisins. The labeled weight of the boxes is 9 oz. The quality control department sampled five boxes at two hour time intervals to construct a control chart. Base your analysis on the eight samples below:
Sample X-bar R
1 8.71 .66
2 8.70 .62
3 8.66 .59
4 8.78 .58
5 8.61 .67
6 8.72 .55
7 8.69 .70
8 8.73 .61
a. Compute the centerline for the x-bar chart. Compute the centerline for the R-chart.
b. Compute the upper and lower control limits for the X-bar chart.
c. Compute the upper and lower AB zone boundary for the x-bar chart.
d. Compute the upper and lower control limits for the R chart.