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Question
The mean and standard deviations of two brands of watches are given below:
| Brand-I | Brand-II | |
| Mean | 36 months | 48 months |
| S.D. | 8 months | 10 months |
Calculate a coefficient of variation of the two brands and interpret the results.
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Solution
Here, `bar("x"_"I") = 36, bar("x"_"II") = 48, sigma_"I" = 8, sigma_"II" = 10`
C.V. (I) = `100 xx sigma_"I"/bar("x"_"I") = 100 xx 8/36` = 22.22%
C.V. (II) = `100 xx sigma_"II"/bar("x"_"II") = 100 xx 10/48` = 20.83%
Since, C.V. (I) > C.V. (II)
∴ brand I is more variable.
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