Question

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

Answer 1

The area of the circular sheet with $4cm$ radius is,

$A=\pi r^2$

$=16\pi$

The area of the circular sheet with $3cm$ radius is,

$A=\pi r^2$

$=9\pi$

Since the circle with radius $3cm$ is removed, then the remaining area is,

$A=16\pi -9\pi$

$=7\pi$

$=7\times 3.14$

$=21.98c{m}^2$