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

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

It is given in the question that,

Standard deviation of mathematics = 12

Also, standard deviation of physics = 15

And, standard deviation of chemistry = 20

We know that,

Hence, subject with highest variability in marks is chemistry as subject with the greater C.V is more variable than others

And, Subject with lowest variability in marks is mathematics