Algebra Exam Scores. One year at Arizona State University, the algebra course director decided to experiment with a new teaching method that might reduce variability in final-exam scores by eliminating lower scores. The director randomly divided the algebra students who were registered for class at 9:40 A.M. into two groups. One of the groups, called the control group, was taught the usual algebra course; the other group, called the experimental group, was taught by the new teaching method. Both classes covered the same material, took the same unit quizzes, and took the same final exam at the same time. The final-exam scores (out of 40 possible) for the two groups are shown in the following table.

Control Experimental 36 35 35 33 32 32 36 35 35 31 31 29 29 28 28 28 30 29 27 27 27 27 27 26 26 25 26 23 21 21 24 24 24 23 20 20 35 32 28 28 19 19 18 18 18 17 25 23 21 19 17 16 15 15 15 15 14 11 10 9 4 Do the data provide sufficient evidence to conclude that there is less variation among final-exam scores when the new teaching method is used rather than the usual one? Perform an F-test at the 5% significance level. (Note: s1 = 7.813 and s2 = 5.286.)