Question

A closed cylindrical tank of radius 7 m and height 3 m is made from a sheet of metal.How much sheet of metal is required?

Answer 1

Given, Radius of cylindrical tank r = 7 m
Height of cylindrical tank h= 3 m
Total surface area of cylindrical tank = 2$\pi$ r(h+r)

$=2\times \frac{22}{7}\times 7(3+7)$
$=44\times 10=440m^2$
Hence $440m^2$metal sheet is required.