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A spherical ball is painted. The radius is then increased so that the new surface area is 44% more than before.
By what percentage was the radius increased?

Class 9Surface Area of a SphereMensuration
  • A20%
  • B22%
  • C44%
  • D11%

Step-by-Step Solution

New area / old area , so new / old , an increase of 20%.
Answer: A) 20%

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