Question

A manufacturer wants to estimate the proportion of defective items in production.18 out of 8,000 randomly sampled items are found to be defective.

a) Establish a 99% confidence interval for the proportion of defective items.

b) If we had constructed a confidence interval for the proportion of non-defective items from of the same data, would we have obtained a greater margin of error?

c) A proportion of defective items of 3/1000 is considered acceptable. Are we sure of meet the standard in this factory with a 99% confidence level? Justify.

Answer #1

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