A direct mailing company sells computers and computer parts

A direct mailing company sells computers and computer parts by mail. The company claims that at least 90% of all orders are mailed within 72 hours after they are received. The quality control department at the company often takes samples to check if this claim is valid. A recently taken random sample of 150 orders showed that 129 of them were mailed within 72 hours. a) Set up the null and alternative hypotheses to test whether the company

Solution

a) Set up the null and alternative hypotheses to test whether the company