Question

Find the volume of a cone having radius of the base 35 cm and slant height 37 cm.

Answer 1

Radius of the base of the cone, r = 35 cm
Slant height of the cone, l = 37 cm

$$\begin{gathered} \mathrm{Now},h=\sqrt{l^2-r^2} \\ =\sqrt{{37}^2-{35}^2} \\ =\sqrt{1369-1225} \\ =\sqrt{144} \\ =12\mathrm{cm} \end{gathered}$$

∴ Volume of the cone = $\frac{1}{3}\mathrm{\pi }{r}^{\mathit{2}}h$
$$\begin{gathered} =\frac{1}{3}\times \frac{22}{7}\times {35}^2\times 12 \\ =22\times 5\times 35\times 4 \\ =15400{\mathrm{cm}}^3 \end{gathered}$$