Let the mean of 6 observations $1,2,4,5, x$ and $y$ be 5 and their variance be 10 . Then $x$ is equa

Question

Let the mean of 6 observations $1,2,4,5, x$ and $y$ be 5 and their variance be 10 . Then $x$ is equal to

Professor PC Thomas Classes · Answer

Sum $= 30 \Rightarrow x+y = 18$. Variance formula setup gives equation in $(x-y)^2$. Solving gives $x=8$ (or 10).