Question 21 • Algebra II
First find the class mean: (90 + 75 + 72 + 88 + 85) ÷ 5 = 82. The numerator is the sum of the squared differences from the mean: 8² + (−7)² + (−10)² + 6² + 3² = 64 + 49 + 100 + 36 + 9 = 258. So the numerator is 258, choice C.
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