Question

Let $𝑋={11,12,13,…,40,41}$ and $𝑌={61,62,63,…,90,91}$ be the two sets of observations. If $\bar 𝑥$ and $\bar 𝑦$ are their respective means and $σ^2$ is the variance of all the observations in $𝑋∪𝑌$, then $|\bar 𝑥+\bar 𝑦−σ^2|$ is equal to ____ .

Answer 1

The answer is 603.