# 8. A horse is tied to a peg at one corner of a square shaped grass field of side 15 m by means of a 5 m long rope (see Fig.). Find  (i) the area of that part of the field in which the horse can graze.

$Area\ =\ \frac{\Theta}{360^{\circ}}\ \times \pi r^2$
$=\ \frac{90^{\circ}}{360^{\circ}}\ \times \pi \times 5^2$
$=\ 19.62\ m^2$