Question

A closed cylindrical tank of radius 7 m and a height 4 m is made from a sheet of metal. How much sheet of metal is required?

• A. $484c{m}^2$
• B. $480c{m}^2$
• C. $220c{m}^2$
• D. $240c{m}^2$

Answer 1

The correct option is A $484c{m}^2$

Required sheet metal = surface area of cylinder
$=2\pi rh+2\pi r^2$

$=2\pi r(r+h)$

$=2\times \frac{22}{7}\times 7(7+4)$

$=44\times 11$

$=484c{m}^2$