A quality control chart is used to monitor the customer wait time at a local call center. Sample means of five times are averaged and plotted over time. The last five sample means show a trend of decreasing sample means. The process is ________.
A)out of control
B)in control
C)improving
D)showing chance variation

Question

Quizplus · Accepted Answer

A decreasing trend in sample means indicates that the process is not in control and there may be factors causing the wait time to decrease. This means that the process is likely to be unstable and out of control.

A Quality Control Chart Is Used to Monitor the Customer