A part that connects two levels should have a distance between the two holes of 4". It has been determined that X-bar and R-charts should be set up to determine if the process is in statistical control. The following ten samples of size four were collected. Calculate the control limits, plot the control charts, and determine if the process is in control.
Mean Range
Sample 1 4.01 0.04
Sample 2 3.98 0.06
Sample 3 4.00 0.02
Sample 4 3.99 0.05
Sample 5 4.03 0.06
Sample 6 3.97 0.02
Sample 7 4.02 0.02
Sample 8 3.99 0.04
Sample 9 3.98 0.05
Sample 10 4.01 0.06