Question

From a circular sheet of radius $4\text{cm}$, a circle of radius $3\text{cm}$ is removed. Find the area of the remaining sheet. (Take $\pi =3.14$)

Answer 1

Radius of circular sheet(R)$=4\text{cm}$ and radius of removed circle(r)$=3\text{cm}$
Area of remaining sheet$=$Area of circular sheet$-$Area of removed circle
$=\pi R^2-\pi r^2=\pi (R^2-r^2)$
$=\pi (4^2-3^2)=\pi (16-9)$
$=3.14\times 7=21.98{\text{cm}}^2$
Thus, the area of the remaining sheet is $21.98{\text{cm}}^2$