Hoping to reduce the variability of the final exam scores in his business statistics classes, an instructor at Miami University in Oxford, Ohio, developed a new set of PowerPoint presentations to use in his classes. One business statistics section was taught using the instructor’s old notes and a second section was taught using the new PowerPoint presentations. The final exam scores earned by the students in the two sections are given in the following table.

Assuming that these two sections represent approximately independent random samples of students, and assuming approximate normality, test to see if the new PowerPoint presentations have reduced the variability of the final exam scores at the .05 level of significance. Explain your conclusion.

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Section 1: Using Old Notes 70 83 69 83 80 57 72 89 76 91 79 76 60 82 90 62 70 84 54 80 Section 2: Using New PowerPoint Slides 78 84 65 74 78 93 96 64 98 64 96 80 96 88 97 79 58 76 66 78 89 69 75 63 73 82 62 83 86 73