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CBSE Class 9 Answered

about area of a circle
Asked by ishmeet kaur Sidana | 08 Jan, 2014, 09:06: PM
answered-by-expert Expert Answer
Let 'r' be the radius of the circle and its area =
When the radius is decreased by 'N', the new radius of the circle = (r - N).
 
Therefore the area of the new circle = .
But it is given as half of the old area.
 
That is,
Answered by Vimala Ramamurthy | 09 Jan, 2014, 09:43: AM

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