Question

The total surface area of a cylinder is 2464 sq cm. The height and radius of the cylinder are equal. Find the radius of its base.

Answer 1

Radius of cylinder (r) = Height of cylinder (h)
Total surface area of cylinder = 2464 sq cm
Total surface area of cylinder = 2πr(r + h)
$$\begin{gathered} \Rightarrow 2464=2\times \frac{22}{7}\times r\left(r+h\right) \\ \Rightarrow r\left(r+h\right)=\frac{2464\times 7}{2\times 22} \\ \Rightarrow r\left(r+r\right)=392 \\ \Rightarrow 2r^2=392 \\ \Rightarrow r^2=196 \\ \Rightarrow r=14\mathrm{cm} \end{gathered}$$