Question

If radii of two cylinders are in the ratio $4:3$ and their heights are in the ratio $5:6$, find the ratio of their curved surfaces.

Answer 1

$\frac{S_1}{S_2}=\frac{2\pi r_1{h}_1}{2\pi r_2{h}_2}=\frac{4\times 5}{3\times 6}=\frac{10}{9}=10:9$