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प्रश्न
The surface area of a sphere is same as the curved surface area of a right circular cylinder whose height and diameter are 12 cm each. The radius of the sphere is
विकल्प
3 cm
4 cm
6 cm
12 cm
उत्तर
Let r be the radius of sphere
But,
Surface area of sphere = C.S.A. of cylinder
`4pir^2 = 2pirh`
`4r^2 = 2 xx 6 xx 12 `
`r^2 = (2 xx 6 xx 12)/4`
`r = 6cm`
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