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प्रश्न
The ratio between the curved surface area and the total surface area of a right circular cylinder is 1 : 2. Prove that its height and radius are equal.
उत्तर
We have,
Let radius of cylinder be 'r'.
Let height of cylinder be 'h'.
`("Curved surface area of cylinder")/("total surface area of cylinder") = 1/2`
`(2pirh)/(2pir(h + r)) = 1/2`
`h/((h + r)) = 1/2`
2h = h + r
2h - h = r
h = r
Height = Radius
Hence proved.
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