The mean and standard deviation of marks obtained by 50 students of a class in three subjects, Mathematics, Physics and Chemistry are given below:

 Subject Mathematics Physics Chemistry Mean 42 32 40.9 Standard deviation 12 15 20

Which of the three subjects shows the highest variability in marks and which shows the lowest?

Asked by Abhisek | 11 months ago |  115

##### Solution :-

Standard deviation of Mathematics = 12

Standard deviation of Physics = 15

Standard deviation of Chemistry = 20

The coefficient of variation (C.V.) is given by = $$\dfrac{Standard \;deviation}{Mean}\times 100$$

C.V. (in Mathematics) = $$\dfrac{12}{42}\times 100=28.57$$

C.V. (in Physics) =$$\dfrac{15}{32}\times 100=46.87$$

C.V. (in Chemistry) =$$\dfrac{20}{40.9}\times 100=48.89$$

The subject with greater C.V. is more variable than others.

Therefore, the highest variability in marks is in Chemistry and the lowest variability in marks is in Mathematics

Answered by Sudhanshu | 11 months ago

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