Fowle Marketing Research, Inc., bases charges to a client on the assumption that telephone surveys can be completed in a mean time of 15 minutes or less. If a longer mean survey time is necessary, a premium rate is charged. Suppose a sample of 35 surveys shows a sample mean of 17 minutes. Use s = 4 minutes. Is the premium rate justified?
a. Formulate the null and alternative hypotheses for this application.
H0: µ
Ha: µ
b. Compute the value of the test statistic (to 2 decimals).
c. What is the p-value (to 4 decimals)?
d. Using a = .01, is a premium rate justified for this client?