Chapter 10.3, Problem 2E

The target fill weight for a box of cereal is 350 g. Each day a sample of 300 boxes is taken, and the number that arc underweight is counted. The number of under-weight boxes for each of the last 25 days is as follows:

23	12	19	19	20	19	21	27	26	23	26	22	25
30	30	22	25	27	29	35	39	43	41	39	29

1. a. Compute the upper and lower 3σ limits for a p chart.
2. b. Is the process in control? If not. when is it first detected to be out of control?