Variance(s$^2$) = $\;{Σ{(x - \ov{x})^2}}/{n}$
But mean = 50 (from question 39 same information)
x
x - $\ov{x}$
(x - $\ov{x})^2$
$∑{(x - \ov{x})^2}$ = 280
Variance(s$^2$) = $\;{Σ{(x - \ov{x})^2}}/{n}$ = $\;{280}/{8}$ = 35
