What is the variance of {9, -4, 7, 10, 3, -2}?

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Answer 1 · 2016-03-27T11:10:10

Variance is 28.472

Mean of #{9, -4, 7, 10, 3, -2}# is

#(9+(-4)+7+10+3+(-2))/6=23/6#

For Variance of a series #{x_1.x_2,...,x_6}#, whose mean is #barx#is given by

#(Sigma(x-barx)^2)/6# and hence it is

#1/6*{(23/6-9)^2+(23/6-(-4))^2+(23/6-7)^2+(23/6-10)^2+(23/6-3)^2+(23/6-(-2))^2}# or

#1/6*{(-31/6)^2+(47/6)^2+(-19/6)^2+(-37/6)^2+(5/6)^2+(35/6)^2}#

= #1/6*{961/36+2209/36+361/36+1369/36+25/36+1225/36}#

= #1/6*(6150/36)=28.472#