Question

the area of the curved surface of a right circular cylinder is 4400cm² and the circumference of the base is 110cm. find the height and radius of cylinder.

Answer 1

$$\begin{gathered} \mathrm{Let}\mathrm{r}\mathrm{be}\mathrm{the}\mathrm{radius}\mathrm{of}\mathrm{base}\mathrm{and}\mathrm{h}\mathrm{be}\mathrm{the}\mathrm{height}\mathrm{of}\mathrm{cylinder}. \\ \mathrm{Now},\mathrm{circumference}\mathrm{of}\mathrm{base}=110\mathrm{cm} \\ \Rightarrow 2\mathrm{\pi r}=110\mathrm{cm} \\ \mathrm{Now},\mathrm{CSA}=4400{\mathrm{cm}}^2 \\ \Rightarrow 2\mathrm{\pi rh}=4400 \\ \Rightarrow 110\mathrm{h}=4400 \\ \Rightarrow \mathrm{h}=40\mathrm{cm} \\ \mathrm{Now},\mathrm{CSA}=4400 \\ \Rightarrow 2\mathrm{\pi rh}=4400 \\ \Rightarrow 2\times \frac{22}{7}\times \mathrm{r}\times 40=4400 \\ \Rightarrow \mathrm{r}=17.5\mathrm{cm} \end{gathered}$$