Question

The base- radius of a cone is 60 cm and the height is 90 cm . Find, correct to three significant figures -
( i) the volume in cubic metres.
(ii)the area of the curved surface in square metres.

Answer 1

$$\begin{gathered} \mathrm{Hi}, \\ \mathrm{volume}\mathrm{of}\mathrm{cone}=\frac{1}{3}{\mathrm{\pi r}}^2\mathrm{h}=\frac{1}{3}\times \frac{22}{7}\times {\left(60\right)}^2\times 90 \\ =100394.366{\mathrm{cm}}^3 \\ \mathrm{and} \\ \mathrm{curved}\mathrm{surface}\mathrm{area}=2\mathrm{\pi rh}=2\times \frac{22}{7}\times 60\times 90 \\ =33942.8571{\mathrm{cm}}^2 \\ \mathrm{Regards} \end{gathered}$$