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
Solution:
(c) 20:27
We have the following:
$\frac{r_{1}}{r_{2}}=\frac{2}{3}$
$\frac{h_{1}}{h_{2}}=\frac{5}{3}$
$\therefore \frac{V_{1}}{V_{2}}=\frac{\pi \mathrm{r}_{1}{ }^{2} \mathrm{~h}_{1}}{\pi \mathrm{r}_{2}{ }^{2} \mathrm{~h}_{2}}=\frac{20}{27}$