Question

The area of the curved surface of a cylinder is $4400c{m}^2$ and the circumference of its base is $110cm$. Find the height of the cylinder.

Answer 1

Circumference of its base $=2\pi r$

$\begin{array}{c}\frac{110}{2}=\frac{22}{7}r\\ 55=\frac{22}{7}r\\ r=\frac{55\times 7}{22}=\frac{35}{2}\end{array}$

Curved surface area of the cylinder $=2\pi rh$

$\begin{array}{c}4400=2\times \frac{22}{7}\times \frac{35}{2}h\\ \frac{4400}{110}=h\\ height=40cm\end{array}$