Question

Find the volume of a cylinder, if the diameter (d) of its base and its altitude (h) are:
(i) d = 21 cm, h = 10 cm
(ii) d = 7 m, h = 24 m

Answer 1

$$\begin{gathered} \left(\mathrm{i}\right)\mathrm{Given}: \\ d=21\mathrm{cm},\mathrm{radius},\mathit{}r=\frac{d}{2}=10.5\mathrm{cm} \\ \mathrm{height},\mathit{}h=10\mathrm{cm} \\ \mathrm{Volume}\mathrm{of}\mathrm{the}\mathrm{cylinder},V=\mathrm{\pi }{r}^{\mathit{2}}h \\ =\frac{22}{7}\times {\left(10.5\right)}^2\times 10 \\ =3465{\mathrm{cm}}^3 \\ \left(\mathrm{ii}\right)\mathrm{Given}: \\ d=7\mathrm{m},\mathrm{radius},r=\frac{d}{2}=3.5\mathrm{m} \\ \mathrm{height}h=24\mathrm{m} \\ \mathrm{Volume}\mathrm{of}\mathrm{the}\mathrm{cylinder},\mathrm{V}=\mathrm{\pi }{r}^{2}h \\ =\frac{22}{7}\times {\left(3.5\right)}^2\times 24 \\ =924{\mathrm{m}}^3 \end{gathered}$$