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The Circumference of a Circle is Numerically Equal to Its Area. Find the Area and Circumference of the Circle.

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Question

The circumference of a circle is numerically equal to its area. Find the area and circumference of the circle.

Sum
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Solution

Let the radius of a circle = r cm
⇒ Circumference of a circle = 2πr cm
Area of a circle = πr2
Now,
Circumference of a circle
= Area of a circle
⇒  2πr = πr2
⇒ 2 = r
Thus, we have
Area of a circle
= πr2
= 3.14 x 2 x 2
= 12.56cm2
Circumference of a circle
= Area of a circle
= 12.56cm2.

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Chapter 24: Perimeter and Area - Exercise 24.3

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Frank Mathematics [English] Class 9 ICSE
Chapter 24 Perimeter and Area
Exercise 24.3 | Q 7

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