Question

The radii of the two cylinders are in the ratio $2:3$ and their heights are in the ratio $5:3$. What is the ratio of their volume?

Answer 1

Formula for olume of cylinder $=\pi r^{2}h$
Let the radii of the base be 2r and 3r, heights as 5h and 3h, respectively
$\therefore$ Ratio of their volumes $=\frac{\pi {\left(2r\right)}^2\times 5h}{\pi {\left(3r\right)}^2\times 3h}=\frac{4\times 5}{9\times 3}=20:27$