A manufacturer uses statistical process control to control the quality of the firm's products. Samples of 50 of Product A are taken, and a defective/acceptable decision is made on each unit sampled. For Product B, the number of flaws per unit is counted. What type(s) of control charts should be used?
A) p-charts for both A and B
B) p-chart for A, c-chart for B
C) c-charts for both A and B
D) p-chart for A, mean and range charts for B
E) c-chart for A, mean and range charts for B

Question

Quizplus · Accepted Answer

For Product A, where a defective/acceptable decision is made, a p-chart (proportion chart) is appropriate because it deals with the proportion of defective items in a sample. For Product B, where the number of flaws per unit is counted, a c-chart (count chart) is used because it is designed for situations where the number of occurrences per unit of measure can be counted; flaws per unit in this case.

A Manufacturer Uses Statistical Process Control to Control the Quality