Question

The sum of 10 values is 100 and the sum of their squares is 1090. Find out the coefficient of variation.

Answer 1

$\sum X=100N=10So,\overline{X}=\frac{\sum X}{N}=\frac{100}{10}=10\sum X^2=1090\sigma =\sqrt{\frac{\sum X^2}{N}-(\overline{X}{)}^2}=\sqrt{\frac{1090}{10}-(10{)}^2}=\sqrt{9}=3CV=\frac{\sigma }{\overline{X}}\times 100=\frac{3}{10}\times 100=30$