During long production runs of canned tomatoes, the average weights (in ounces) of samples of five cans of standard- grade tomatoes in pureed form were taken at 30 control points during an 11-day period. These results are shown in the table. When the machine is performing normally, the average weight per can is 21 ounces with a standard deviation of 1.20 ounces.

a. Compute the upper and lower control limits and the centerline for the xÌ… chart.

b. Plot the sample data on the xÌ… chart and determine whether the performance of the machine is in control.

Transcribed Image Text:

Sample Average Number Weight Sample Average Number Weight 23.1 21.3 1 16 21.4 2 17 20.4 22.0 18 22.8 21.4 19 21.1 21.8 20 20.7 21.6 20.6 21 20.1 22 22.4 8. 21.4 23 21.3 21.5 24 21.1 10 20.2 25 20.1 11 20.3 26 21.2 12 20.1 27 19.9 13 21.7 28 21.1 14 21.0 29 21.6 15 21.6 30 21.3