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प्रश्न
Two right circular solid cylinders have radii in the ratio 3 : 5 and heights in the ratio 2 : 3. Find the ratio between their curved surface areas.
उत्तर
Let the radii and height of two right circular cylinders be r1, r2 and h1, h2 respectively.
It is given that,
`r_1/r_2 = 3/5` and `h_1/h_2 = 2/3`
`"Curved surface area of cylinder 1"/"Curved surface area of cylinder 2" = (2pir_1h_1)/(2pir_2h_2)`
= `(r_1/r_2) xx (h_1/h_2)`
= `3/5 xx 2/3`
= `2/5`
∴ Ratio between their curved surface areas is 2 : 5.
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