1. You are interested in testing whether a particular brand of floppy disks has more than 5% defectives. A random sample of n = 325 disks contains 18 defectives.
(a) State the null and the alternative hypotheses.
(b) Conduct the test by computing a p-value.
2. The time between telephone calls at a company switchboard has an exponential distribution with mean of 3 minutes.
(a) Find the probability that the average of 45 of these times is less than 2.5 minutes.
(b) Find the 0.15 quantile for the average of 45 of these times.