# Question: A control chart is to be established on a process

A control chart is to be established on a process producing refrigerators. The inspection unit is one refrigerator, and a common chart for nonconformities is to be used. As preliminary data, 16 non Use a c chart for nonconformities with an inspection unit n = 1 refrigerator.

Conformities were counted in inspecting 30 refrigerators.

(a) What are the three-sigma control limits?

(b) What is the a-risk for this control chart?

(c) What is the β-risk if the average number of defects is actually 2 (i.e., if c = 2.0)?

(d) Find the average run length if the average number o defects is actually 2.

Conformities were counted in inspecting 30 refrigerators.

(a) What are the three-sigma control limits?

(b) What is the a-risk for this control chart?

(c) What is the β-risk if the average number of defects is actually 2 (i.e., if c = 2.0)?

(d) Find the average run length if the average number o defects is actually 2.

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