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For a set of 10 observations with mean 50, the total of the squared deviations from the mean is 250. What is the coefficient of variation?
- 50%
- 10%
- 40%
- None of these
Correct answer: 10%
Solution
Variance = 250/10 = 25 so SD = 5. Coefficient of variation = (SD/mean) x 100 = (5/50) x 100 = 10%.
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