If the diameters of a circle is increased by 100% . Its

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If the diameters of a circle is increased by 100% . Its area is increased by ?

1. 100%
2. 200%
3. 300%
4. 400%

Correct Option: C

Original area = π(d/2)²
= (πd²) / 4

New area = π(2d/2)²
= πd²

Increase in area = (πd² - πd²/4)
= 3πd²/4

∴ Required increase percent
= [(3πd²)/4 x 4/(πd²) x 100]%
= 300%