Question

A piece of wire in the shape of a rectangle of length $7cm$ and breadth $4cm$ is refolded in the form of a circle. Find the radius of the circle.

Answer 1

Length of rectangle = 7 cm

Breadth of rectangle = 4 cm

Perimeter of rectangle = circumference of circle

$2(l+b)=2\pi r$

$11cm=(\frac{22}{7}\times r)cm$

$r=\frac{11\times 7}{22}=\frac{7}{2}cm$

$r=3.5cm$