Suppose the average length of stay in a particular hospital is known to be 60 days for lung cancer patients with an estimated variance of 225.
a. What is the probability that a random sample of size n = 5 will produce a mean stay greater than 75 days? To answer this, it will help if you write down what is given and what you need to find.
b. What is the probability that a random sample of size n = 25 will produce a mean stay more than 5 days off from the known mean of 60 days? To answer this, it will help if you write down what is given and what you need to find.