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प्रश्न
If radius of a circle is increased to twice its original length, how much will the area of the circle increase?
विकल्प
1.4 times
2 times
3 times
4 times
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उत्तर
4 times
Explanation:
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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