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Mean of frequency distribution Σf_i x_i / Σf_i. Find mean of: 2(×3), 4(×5), 6(×2): values 2,4,6 with frequencies 3, 5, 2:
A4
B6
C(6+20+12)/10 = 38/10 = 3.8
D5
Answer & Solution
Correct answer: C. (6+20+12)/10 = 38/10 = 3.8
Σf_i = 10. Σf_i x_i = 2(3) + 4(5) + 6(2) = 6 + 20 + 12 = 38. Mean = 38/10 = 3.8.
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