A hospital is hoping to introduce a Fast Care Unit. The hospital claims that after the initial run, 87% of the patients were pleased with the service. We ask 20 randomly selected patients whether or not they are pleased with the service.
(a) Is this a binomial experiment? Explain how you know.
(b) Use the correct formula to find the probability that, out of 20 patients, exactly 15 are pleased with the service. Show your calculations or explain how you found the probability.