Question

The difference between the circumference and radius of a circle is 37 cm. The area of the circle is

(a) 111${cm}^2\left(b\right)184{cm}^2\left(c\right)154{cm}^2\left(d\right)259c{m}^2$

Answer 1

Taking pi as 3.14 will give an approximate answer. You can do it by taking $\frac{22}{7}$ as well

Let the radius be r cm

Circumference will be,
$2\pi r=2\times 3.14\times r=6.28\times r$

According to the question

$\Rightarrow 2\pi r-r=37$

6.28r- 1r =37
5.28r = 37
$\Rightarrow r=\frac{37}{5.28}$
$\Rightarrow r=approx.7cm$

$\therefore Area=\pi r^2=3.14\times 7\times 7=154$
Answer= 154 ${cm}^2$