\begin{align*} & \frac{1}{4} \left ( (2-6.25)^2 + (5-6.25)^2 + (8-6.25)^2 + (10-6.25)^2 \right ) \\ & = \frac{18.0625 + 1.5625 + 3.0625 + 14.0625}{4} \\ & = \frac{36.75}{4}\\ & = 9.1875. \end{align*}