A finishing process packages assemblies into boxes. You have noticed variability in the boxes and desire to improve the process to fix the problem because some products fit too tightly into the boxes and others fit too loosely.
Following are width measurements for the boxes.
Sample
1 68.51 68.46 68.54 68.34 68.46 68.46
2 68.94 68.94 68.54 68.56 68.70 68.70
3 68.66 68.44 68.55 68.77 68.70 68.64
4 68.49 68.94 68.56 68.62 68.69 68.56
5 68.64 68.63 68.62 68.32 68.34 68.24
6 68.32 68.42 68.99 68.02 68.03 68.47
7 68.99 68.94 68.95 68.95 68.94 68.97
8 68.92 68.91 68.97 68.93 68.96 63.95
Using x-bar and R charts, plot and interpret the process.