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Find the variance of the following frequency distribution. Class: 0-2, 2-4, 4-6, 6-8, 8-10, 10-12 Frequency f_i: 2, 7, 12, 19, 9, 1
- 4.97
- 4.79
- 4.57
- 5.97
Correct answer: 4.97
Solution
Mean = 308/50 = 6.16; sum f_i x_i² = 2146; variance = 2146/50 - 6.16² = 42.92 - 37.9456 ~ 4.97.
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