Question

The surface area of a sphere is 5544 cm². Find its volume.

Answer 1

$$\begin{gathered} \mathrm{Let}\mathrm{the}\mathrm{radius}\mathrm{of}\mathrm{the}\mathrm{sphere}=\mathrm{r} \\ \mathrm{Now},\mathrm{surface}\mathrm{area}\mathrm{of}\mathrm{sphere}=5544{\mathrm{cm}}^2 \\ \Rightarrow 4{\mathrm{\pi r}}^2=5544 \\ \Rightarrow {\mathrm{\pi r}}^2=1386 \\ \Rightarrow \frac{22}{7}\times {\mathrm{r}}^2=1386 \\ \Rightarrow {\mathrm{r}}^2=\frac{1386\times 7}{22} \\ \Rightarrow {\mathrm{r}}^2=441 \\ \Rightarrow \mathrm{r}=21\mathrm{cm} \\ \mathrm{Now},\mathrm{volume}=\frac{4}{3}{\mathrm{\pi r}}^3=\frac{4}{3}\times \frac{22}{7}\times 21\times 21\times 21=38808{\mathrm{cm}}^3 \end{gathered}$$