Here, we have to choose the option which will give the coefficient of variation as 30%
Option A: When mean is 30 and standard deviation is 15
As we know, Coefficient of variation
=×100 ⇒ Coefficient of variation
=×100=50% Hence, option A is not the correct answer.
Option B: When mean is 4 and standard deviation is 16
As we know, Coefficient of variation
=×100 ⇒ Coefficient of variation
=×100=400% Hence, option B is not the correct answer.
Option C: When mean is 3 and standard deviation is 3
As we know, Coefficient of variation
=×100 ⇒ Coefficient of variation
=×100=100% Hence, option
C is not the correct answer.
Option D: When mean is 10 and standard deviation is 3
As we know, Coefficient of variation
=×100 ⇒ Coefficient of variation
=×100=30% Hence, option D is the correct answer.