The mean cleanup and redecorating time for one-bedroom student apartment at campus Housing is 16 hours. The time for the cleanup and redecorating process follows the normal distribution. The campus Housing administration instituted a "fee and fine system" that encourages students to clean their apartments when they vacate them. This should shorten the cleanup and redecorating time. A sample of 20 apartments had a mean cleanup and redecorating time of 13.5 hours with a standard deviation of 1.5 hours. Does use of the "fee and fine system" decrease the cleanup and redecorating time? Follow a hypothesis testing procedure using the 0.05 significance level.
a. State the null and alternate hypothesis
b. What is the level of significance?
c. What is the critical value?
d. Compute the value of the test statistic
e. What is your decision regarding the null hypothesis? Interpret the result.