Complete the variance and standard deviation of the following observations of marks of 5 students of a tutorial group: Marks out of 25:8,12,13,15,22

Explanation

`bar X=frac{8+12+13+15+22}{5}=14`

`x_i-bar X :` -6, -2, -2, 1, 8

`Variance =frac{1}{N}sum_(i=1)^(5)(x_1-bar X)^2=frac{106}{5}=21.2`

Standard deviation`=sqrt(variance)=sqrt(21.2)=4.6`