Q30 of 131 Page 226

If radius of a circle is increased to twice its original length, how much will the area of the circle increase?

Let r be the radius of the circle.


∴ Area of circle = π2


If radius is increased to twice its original length, then radius will be 2r.
Now, area of new circle = π(2r)2 = 4π2 = 4 times of original area
Hence, the area of circle will be increased by 4 times

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