Use the t-test

Correct the question then use the F-testQuestion2:

Past experience indicates that the time for high school seniors to complete standardized test is a normal random variable with a standard deviation of 6 minutes. Test the hypothesis that a=6 against the alternative that a= 6 if a random sample of 20 high school seniors has a standard deviation s=4.51. Use a 0.05 level of significance.

RonL