Question

Find the circumference of the circle whose radius is $28$ mm. Take $\pi =\frac{22}{7}$.

Answer 1

Let $r$ be the radius of the circle.

Then according to the problem we've $r=28$.

Then perimeter will be $\left(P\right)=2\pi r$

$P=2\times \frac{22}{7}\times 28$

$P=176$ mm.

So the perimeter of the circle is $176$ mm.