SOLUTION: Explain why the sum of the deviations from the mean is always equal to zero?

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Question 384376: Explain why the sum of the deviations from the mean is always equal to zero?
Answer by Jk22(389) About Me  (Show Source):
You can put this solution on YOUR website!
If xi were the datas, and x the average, x=(x1+...+xn)/n

the deviation were then dxi=xi-x

the sum of deviations : dx1+...+dxn=x1+...+xn-nx but nx=x1+...+xn
hence dx1+...dxn=x1+...xn-x1-...-xn=0