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For a Class XI section the following data are recorded: heights have Mean = 162.6 cm and Variance = 127.69 cm²; weights have Mean = 52.36 kg and Variance = 23.1361 kg². Do the weights show greater variation than the heights?
- Yes, because the variance of weights is greater than that of heights.
- No, because the coefficient of variation of heights is greater than that of weights.
- Yes, because the coefficient of variation of weights is greater than that of heights.
- No, because the mean of heights is greater than that of weights.
Correct answer: Yes, because the coefficient of variation of weights is greater than that of heights.
Solution
CV(heights) = (11.3/162.6)*100 ~ 6.95% and CV(weights) = (4.81/52.36)*100 ~ 9.19%; weights have higher CV, so greater variation.
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