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? [4 MARKS]

Answer 1

Formula: 1 Mark
Solution: 3 Marks

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

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

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

$=44\times 11$

$=484c{m}^2$