The control limits for an R chart are set at:
A) one mean distance from the average
B) -1 and +1
C) approximately three standard deviations from the average
D) 0 and +1

Question

The control limits for an R chart are set at:
A) one mean distance from the average 
B) -1 and +1 
C) approximately three standard deviations from the average 
D) 0 and +1

Quizplus · Accepted Answer

Control limits on an R chart are typically set at approximately three standard deviations from the average range. This is because the range is indicative of the variation in the process, and using three standard deviations ensures that the chart is properly sensitive to any changes in the process.

The Control Limits for an R Chart Are Set At