QQuestion
The ratio of the length of radius of two solid right circular cylinders is 2:3 and the ratio of their heights is 5:3. Find the ratio of the area of curved surfaces.
The ratio of the length of radius of two solid right circular cylinders is 2:3 and the ratio of their heights is 5:3. Find the ratio of the area of curved surfaces.
The curved surface area (CSA) of a cylinder = 2πrh.
For the first cylinder, let r₁ = 2k and h₁ = 5m;
For the second, r₂ = 3k and h₂ = 3m.
Thus, CSA₁ : CSA₂ = (2π×2k×5m) : (2π×3k×3m)
= 10km : 9km
= 10 : 9.
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