Perfect squares

The lowest perfect square three digit integer is 100, and the highest is 961.

Thus, we need to find $\sum_{i=10}^{31}$ $n^{2}$

Note that $\sum_{i=10}^{31}$ $n^{2}$ = $\sum_{i=1}^{31}$ $n^{2}$ - $\sum_{i=1}^{9}$ $n^{2}$

Evaluate using this equality.