Assignment:
Construct the 3-sigma x-chart and the 3-sigma R-chart
Q: Auto pistons at Yongpin Zhou's plant in Shanghai are produced in a forging process, and the diameter is a critical factor that must be controlled. From sample sizes of 10 pistons produced each day, the mean and the range of this diameter have been as follows:
Day Mean(mm) Range(mm)
1 156.9 4.2
2 153.2 4.6
3 153.6 4.1
4 155.5 5.0
5 156.6 4.5
Construct the 3-sigma x-chart and the 3-sigma R-shart for this dimension, using the data observed in the table above