Professor Fair believes extra time does not improve grades on exams. He randomly divided a group of 300 students into two groups and gave them all the same test. One group had exactly one hour in...

Professor Fair believes extra time does not improve grades on exams. He randomly divided a group of 300 students into two groups and gave them all the same test. One group had exactly one hour in which to finish the test, and the other group could stay as long as desired. The results are shown in the table below. Test at the 0.01 level of significance that time to do a test and tests results are independent.