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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?

1. Yes, because the variance of weights is greater than that of heights.
2. No, because the coefficient of variation of heights is greater than that of weights.
3. Yes, because the coefficient of variation of weights is greater than that of heights.
4. 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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