Question

Calculate circumference of a circle from given information:

No.	Radius $\left(r\right)$	Diameter $\left(d\right)$	Circumference
$\left(1\right)$	$70cm$	__________	__________
$\left(2\right)$	___________	$14metre$	__________
$\left(3\right)$	$49metre$	___________	__________
$\left(4\right)$	$3.5cm$	___________	__________
$\left(5\right)$	___________	$42metre$	__________
$\left(6\right)$	___________	$5.6cm$	__________

Answer 1

As we know $d=2r$ and $circumference=2\pi r$

Therefore we get the answers as below

$\left(1\right)140cm,440cm$
$\left(2\right)7metre,44metre$
$\left(3\right)98m,308metre$
$\left(4\right)7cm,22cm$
$\left(5\right)21metre,132metre$
$\left(6\right)2.8cm,17.6cm$.