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Question
The means and standard deviations of heights ans weights of 50 students of a class are as follows:
| Weights | Heights | |
| Mean | 63.2 kg | 63.2 inch |
| Standard deviation | 5.6 kg | 11.5 inch |
Which shows more variability, heights or weights?
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Solution
\[\text{ Coeffient of variations (CV) in weights } = \frac{SD}{Mean} \times 100\]
\[ = \frac{5 . 6}{63 . 2} \times 100\]
\[ = 8 . 86\]
\[\text{ Coefficient of variations (CV) in heights } = \frac{11 . 5}{63 . 2} \times 100\]
\[ = 18 . 19\]
CV in heights is greater than CV in weights.
Thus, heights will show more variability than weights.
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