## Book: RS Aggarwal - Mathematics

### Chapter: 18. Area of Circle, Sector and Segment

#### Subject: Maths - Class 10th

##### Q. No. 1 of Exercise 18B

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1
##### The circumference of a circle is 39.6 cm. Find its area.

In order to solve such type of questions we basically need to find the radius of the give circle and simply use it to find the area of the given circle.

Given the circumference or perimeter of the circle = 39.6 cm.

And we know, Perimeter or circumference of circle = 2πr

Where, r = Radius of the circle

Therefore, 2πr = 39.6

(put value of π = 22/7)

On rearranging we get,

r = 6.3 cm

So, the radius of the circle = 6.3 cm

And we also know, Area of the circle = πr2

Where, r = radius of the circle

Area of the circle = π(6.3)2

(putting value of r)

= 22×5.67

= 124.74 cm2

The area of the circle = 124.74 cm2.

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