Question:

Develop a p-chart with a Z=3

(if the lower control limit is negative, round the LCL to zero and all other answers to 3 decimal places, e.g. 15.250).

CL=?

UCL=?

LCL=?

Please help me solve, thank you in advance :)

A tire manufacturer has been concerned about the number of defective tires found recently. In order to evaluate the true magnitude of the problem, a production manager selected ten random samples of 20 units each for inspection. The number of defective tires found in each sample are as follows