To set up a p chart to monitor a process that produces computer chips, samples of 300 chips are taken daily, and the number of defective chips in each sample is counted. The numbers of defective chips for each of the last 20 days are as follows:

a. Compute the upper and lower 3σ limits for a p chart.
b. At which sample is the process first detected to be out of control?
c. Suppose that the special cause that resulted in the out-of-control condition is determined. Should this cause be remedied? Explain.

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