Question

Find the circumference of the inner and outer circle as shown in the figure. Take $\pi =3.14$

• A. $56.52$ m, 119.32$ m
• B. $50.52$, $119.32$ m
• C. $56.52$ m, $122$ m

Answer 1

The correct option is A $56.52$ m, 119.32$ m


The radius of the outer circle
$=19m$

Radius of the inner circle
$=19-10=9m$

Circumference of a circle
$=2\pi r$

Circumference of the inner circle
$=2\times 3.14\times 9$

$=18\times 3.14=56.52m$

Circumference of the outer circle
$=2\times 3.14\times 19$

$=38\times 3.14$

$=119.32m$