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Question
Given below is the information about marks obtained in Mathematics and Statistics by 100 students in a class. Which subject shows A the highest variability in marks?
| Mathematics | Statistics | |
| Mean | 20 | 25 |
| S.D. | 2 | 3 |
Solution
Here, `bar("x"_"m")` = 20, `bar("x"_"s")` = 25, σm = 2, σs = 3
C.V. (M) = `(sigma_"m")/(bar("x"_"m"))xx100`
=`(2)/(20) xx 100`
= 10%
C.V. (S) = `(sigma_"s")/(bar("x"_"s"))xx100`
=`(3)/(25) xx 100`
= 12%
Since, C.V. (S) > C.V. (M)
∴ The subject statistics shows higher variability in marks.
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