Answered

the heights, x cm, of the 10 girls in an athletics team are such that 
sum of x (∈x) =1550 and ∈x∧2= 241250

a- find the mean and variance
b- one girl, who is 173cm tall, drops out of the tem. calculate the mean and variance of the heights of the remaining nine members of the team



Answer :

Gwenuin
use the standard deviation equation attached to work this one out. They have given you totalX^2 and sum of X and n, just substitute and work through.
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