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Two distributions have coefficients of variation 50 and 60, and their arithmetic means are 30 and 25, respectively. What is the difference between their standard deviations?
- 0
- 1
- 1.5
- 2.5
Correct answer: 0
Solution
The coefficient of variation is calculated as the ratio of the standard deviation to the mean. Since both distributions have different means but their coefficients of variation indicate that their relative variability is the same, the standard deviations must also be equal, resulting in a difference of 0.
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