Sample Means and Ranges Were Obtained for Five Samples of 10

Multiple Choice

Sample means and ranges were obtained for five samples of 10 units per sample from a production process. Assume the process was considered to be in control during the period these samples were collected. The results are as follows:

-What is the central line of the R chart for this process?

A) 0.23
B) 0.19
C) 0.44
D) 0.25
E) 0.06