Question

What is the variance of {51, 3, 9, 15, 3, -9, 20, -1, 5, 3, 2}?

Answer 1

Variance`" " "sigma^2=27694/121=228.876`

Explanation:

Compute the mean `barx` first

`barx=(51+3+9+15+3+(-9)+20+(-1)+5+3+2)/11=101/11`

Variance`" " "sigma^2=(sum(x-barx)^2)/n`

`" " "sigma^2`
#=((51-101/11)^2+(3-101/11)^2+(9-101/11)^2+(15-101/11)^2+ (3-101/11)^2+(-9-101/11)^2+(20-101/11)^2+(-1-101/11)^2+(5-101/11)^2+ (3-101/11)^2+(2-101/11)^2)/11#

`" " "sigma^2=27694/121=228.876`

God bless....I hope the explanation is useful.