Students use many kinds of criteria when selecting courses. "Teacher who is a very easy grader" is often one criterion.

Students use many kinds of criteria when selecting courses. “Teacher who is a very easy grader” is often one criterion. Three teachers are scheduled to teach statistics next semester. A sample of previous grade distributions for these three teachers is shown here. Professor Grades #1 #2 #3 A 11 13 25 B 14 28 25 C 35 28 13 Other 25 40 21

(a) At the 0.01 level of significance, is there sufficient evidence to conclude “The distribution of grades is not the same for all three professors?” (i) Find the test statistic. (Give your answer correct to two decimal places.)

(ii) Find the p-value. (Give your answer bounds exactly.)

< p <

(iii) State the appropriate conclusion. Fail to reject H0. The distribution of grades is the same for all professors at the 0.01 level of significance. Fail to reject H0. The distribution of grades is not the same for all professors at the 0.01 level of significance. Reject H0. The distribution of grades is the same for all professors at the 0.01 level of significance. Reject H0. The distribution of grades is not the same for all professors at the 0.01 level of significance.

(b) Which professor is the easiest grader? Professor #1 Professor #2 Professor #3 There is no evidence that one is easier than the others.

Students use many kinds of criteria when selecting courses. "Teacher who is a very easy grader" is often one criterion.