A machine at the Pacific Fruit Company fills boxes with
raisins. The labeled weight of the boxes is 9 ounces. The

company wants to construct an R-chart to monitor the fill-
ing process and make sure the box weights are in control.

The quality-control department for the company sampled
five boxes every two hours for three consecutive working
days. The sample observations are as follows:

Construct an R-chart from these data with 3 control lim-
its, plot the sample range values, and comment on process

control.

Samples Box Weights (oz)
1 9.06 9.13 8.97 8.85 8.46
2 8.52 8.61 9.09 9.21 8.95
3 9.35 8.95 9.20 9.03 8.42
4 9.17 9.21 9.05 9.01 9.53
5 9.21 8.87 8.71 9.05 9.35
6 8.74 8.35 8.50 9.06 8.89
7 9.00 9.21 9.05 9.23 8.78
8 9.15 9.20 9.23 9.15 9.06
9 9.98 8.90 8.81 9.05 9.13
10 9.03 9.10 9.26 9.46 8.47
11 9.53 9.02 9.11 8.88 8.92
12 8.95 9.10 9.00 9.06 8.95