Q10 of 157 Page 819

Find the radius of a circle whose perimeter and area are numerically equal.

Given:

Perimeter of circle = Area of circle …… (i)


∵ Perimeter of circle = 2πr and Area of circle = πr2


∴ Using (i), we have


2πr = πr2


2 =


2 = r or r = 2


Hence, the radius of the circle is 2 cm.


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