posted by Dave .
Twelve samples, each containing five parts, were taken
from a process that produces steel rods. The length of each rod in the
samples was determined. The results were tabulated and sample
means and ranges were computed. The results were:
A) Determine the upper and lower control limits and the overall
means for Ẋ charts and R - Charts.
B) Draw the charts and plot the values of the sample means and
C) Do the data indicate a process that is in control?
D) Why or why not?