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Question
Find the ratio between the total surface area of a cylinder to its curved surface area, given that its height and radius are 7.5 cm and 3.5 cm.
Solution
For cylinder, total surface Area = 2πr (h +r )
Curved surface area = 2πrh
`"Total surface area"/"Curved surface area" = (2πr(h+r))/(2πrh) = (h+r)/h`
`"Total surface area"/"curved surface area" = (7.5 +3.5)/7.5=11/7.5`
`(11×15)/7.5 = 22/15 =22:15`
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