Question: Package Delivery

A package-delivery service advertises that at least 90% of all packages brought to its office by 9 A.M. for delivery in the same city are delivered by noon that day. Let p denote the true hypotheses

H0: p = 0.9 versus

HA: p < 0.9

If only 80% of the packages are delivered as advertised, how likely is it that a level 0.01 test based on n = 225 packages will detect such a departure from H0?