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Two distributions have coefficients of variation 60 and 70, and their standard deviations are 21 and 16, respectively. What are their arithmetic means?
- 35,22.85
- 22.85,35.28
- 36,22.85
- 35.28,23.85
Correct answer: 35,22.85
Solution
Coefficient of variation CV = (SD/Mean)*100, so Mean = SD*100/CV. First: 21*100/60 = 35. Second: 16*100/70 = 22.857 ≈ 22.85. The means are 35 and 22.85.
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