Question

The curved surface area of a right circular cylinder is 4.4 m². If the radius of its base is 0.7 m, find its (i) height and (ii) volume.

Answer 1

Radius of the cylinder, r = 0.7 m

Curved surface area of cylinder = 4.4 m²

(i) Let the height of the cylinder be h m.

$$\begin{gathered} \therefore 2\mathrm{\pi }rh=4.4 \\ \Rightarrow 2\times \frac{22}{7}\times 0.7\times h=4.4 \\ \Rightarrow h=\frac{4.4\times 7}{2\times 22\times 0.7}=1\mathrm{m} \end{gathered}$$

Thus, the height of the cylinder is 1 m.

(ii) Volume of the cylinder = $\mathrm{\pi }{r}^{2}h=\frac{22}{7}\times {\left(0.7\right)}^2\times 1$ = 1.54 m³

Thus, the volume of the cylinder is 1.54 m³.