Question

Find the radius of a circle whose circumference is $39.6cm$

Answer 1

Circumference of a circle$=2\pi r=39.6$cm

$\Rightarrow 2\times \frac{22}{7}r=39.6$

$\Rightarrow r=\frac{39.6\times 7}{2\times 22}=6.3‬$cm