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प्रश्न
Two right circular cylinders of equal volumes have their heights in the ratio 1 : 2. What is the ratio of their radii ?
उत्तर
Let r1 and r2 be the radii of two right circular cylinders and h1 and h2 be the heights.
Since,
Both the cylinder has the same volume.
Therefore,
`pir_1^2 h_1 = pir_2^2 h_2`
`(r_1/r_2)^2 = h^2/h_1`
`(h_1 :h_2 = 1:2 , "given")`
`(r_1/r_2)^2 = (2/1)`
`r_1 :r_2 = sqrt2 : 1`
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