Question

Question 80 (ii)

Rani bought a new field that is next to one she already owns in the given figure. This field is in the shape of a square of side 70 m. She makes a semi-circular lawn of maximum area in this field.

Find the area of the square field excluding the lawn.

Answer 1

Given, side of a square = 70 m

Area of square = Side $\times$ Side $=70\times 70=4900m^2$
$\therefore$ Required area =Area of square -Area of semi-circle
$=4900-\frac{1}{2}\times \pi \times \left(35{)}^2\right[\because$ area of semi-circle $=\frac{1}{2}\pi r^2]$
$=4900-\frac{1}{2}\times \frac{22}{7}\times 35\times 35=4900-1925=2975m^2$