Suppose you are planning to carry out a z-test, testing:
H0: mu = 100
H1: mu not equal to 100
and using an alpha level of .05. The population standard deviation is sigma = 60, and you are using a sample of size n = 36. In this situation, the probability of a Type I error (incorrectly rejecting a true null hypothesis) is 5% (i.e., the same value as the alpha level). Suppose that the actual mean value in the population is mu =120 , what is the probability of a Type II error (incorrectly accepting a false null hypothesis)?