Question

A manufacturer of compact disk players uses a set of comprehensive tests to access the electrical function of its product. All compact disk players must pass all tests prior to being sold. A random sample of 500 disk players resulted in 15 failing one or more tests.

(a) Find a 99% two-sided confidence interval on the true proportion of test failure.

(b) Find a 95% confidence lower bound on the true proportion of test failure.

(c) Calculate the sample size if wish to be at least 95% confident that the error in estimating the true proportion in the two-sided confidence interval is less than 0.1, regardless of the true proportion.

Answer 1