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Question
There is surface area and volume of a sphere equal, find the radius of sphere.
Solution
Let the radius of sphere = r
∵ Volume of sphere = Surface area of sphere
`4/3` πr3 = 4 πr2
⇒ r3 = `(4 πr^2 xx 3)/4π`
⇒ r3 = 3r2
⇒ r = 3 cm
Hence, the radius of sphere = 3 cm.
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