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Question
Two right circular solid cylinders have radii in the ratio 3 : 5 and heights in the ratio 2 : 3. Find the ratio between their volumes.
Solution
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`
`"Volume of cylinder 1"/"Volume of cylinder 2" = (pi(r_1)^2h_1)/(pi (r_2)^2 h_2)`
= `(r_1/r_2)^2 xx (h_1/h_2)`
= `(3/5)^2 xx 2/3`
= `9/25 xx 2/3`
= `18/75`
= `6/25`
∴ Ratio between their volumes is 6 : 25.
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