Question

Question 15
Find the circumference of the inner and the outer circles, shown in the adjoining figure.
$(Take\pi =3.14)$

Answer 1

Radius of outer circle (r) =19 m
$\therefore$ Circumference of outer circle= $2\pi r=2\times 3.14\times 19$
= 119.32 m
Now radius of inner circle $\left(r^{{}^{\prime }}\right)=19-10=9m$
$\therefore$ Circumference of inner circle = $2\pi r^{{}^{\prime }}=2\times 3.14\times 9=56.52m$
Therefore the circumferences of inner and outer circles are 56.52 m and 119.32 m respectively