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 coefficient of variation of the two brands and i - Mathematics and Statistics

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Sum

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.

Concept: Coefficient of Variation
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Chapter 2: Measures of Dispersion - Miscellaneous Exercise 2 [Page 35]

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Balbharati Mathematics and Statistics 2 (Commerce) 11th Standard HSC Maharashtra State Board
Chapter 2 Measures of Dispersion
Miscellaneous Exercise 2 | Q 15 | Page 35

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