Question

Tick (✓) the correct answer:
The ratio of the radii of two cylinders is 2 : 3 and the ratio of their heights is 5 : 3. The ratio of their volumes will be
(a) 4 : 9
(b) 9 : 4
(c) 20 : 27
(d) 27 : 20

Answer 1

(c) 20:27

$$\begin{gathered} \mathrm{We}\mathrm{have}\mathrm{the}\mathrm{following}: \\ \frac{r_1}{r_2}=\frac{2}{3} \\ \frac{h_1}{h_2}=\frac{5}{3} \\ \therefore \frac{V_1}{V_2}=\frac{{{\mathrm{\pi r}}_1}^2{\mathrm{h}}_1}{{{\mathrm{\pi r}}_2}^2{\mathrm{h}}_2}=\frac{20}{27} \end{gathered}$$