Q2 of 157 Page 846

The area of a circle is 49π cm2. Its circumference is

Let the radius if circle be r


Given, Area of circle = 49π cm2


Area of circle = πr2


πr2 = 49π


Since = 22/7


∴ πr2 = 49π


⇒ r2 = 49


⇒ r = √49 = 7 cm


∴ Radius of circle = 7 cm


Circumference of circle = 2πr


= 2 × π × 7 cm


= 14π cm


∴ Circumference of the circle is 14π cm

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