Question 8.87

8.87 Does the new process give a better product?

Twelve percent of the products produced by an industrial process over the past several months fail to conform to the specifications. The company modifies the process in an attempt to reduce the rate of nonconformities. In a trial run, the modified process produces 16 nonconforming items out of a total of 300 produced. Do these results demonstrate that the modification is effective? Support your conclusion with a clear statement of your assumptions and the results of your statistical calculations.

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8.87

We are assuming items are independent and the 300 produced represent a random sample for the modified process. . The data show significant evidence that the proportion of nonconforming items in the modified process is less than 12%; the modification was effective.