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प्रश्न
The radii of two cylinders are in the ratio 3 : 5. If their heights are in the ratio 2 : 3, then the ratio of their curved surface areas is
पर्याय
2 : 5
5 : 2
2 : 3
3 : 5
उत्तर
Given that
`r_1 : r_2 = 3: 5` and `h_1 : h_2 = 2 : 3`
Then,
The ratio of C.S.A. of cylinders
`s_1 /s_2 = (2pir_1h_1) / (2pir_2h_2)`
`s_1/s_2 = (r_1/r_2) xx (h_1/h_2)`
`= 3/5 xx 2/3`
`s_1 /s_2 = 2/3`
`s_1 :s_2 = 2:5`
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