Question

It is required to make a closed cylindrical tank of height $1m$ and base diameter $140cm$ from a metal sheet. How many square metres of the sheet are required for the same?

Answer 1

Given: Height of cylindrical tank $\left(h\right)$ is $1m$ and
Diameter $\left(d\right)$ is $140cm$.

$\therefore Radius\left(r\right)=\frac{d}{2}=70cm=0.7m$

Area of the sheet required
= Total surface area $=2\pi r(r+h)$

$=2\times \frac{22}{7}\times 0.7(0.7+1)$

$=2\times 22\times 0.1\times 1.7m^2$

$=7.48m^2$

Hence, total area of sheet required is $7.48m^2$.