Question

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

Answer 1

total surface area of the cylinder
= 2x22/7x140/2(140/2+100)
=2x22/7x70x170
=74800 cm
=748m

Answer 2

$\huge \underline \mathbb {SOLUTION:-}$

Let h be the height and r be the radius of a cylindrical tank.

Height of cylindrical tank, h = 1m

Radius = half of diameter = (140/2) cm = 70 cm = 0.7m

Area of sheet required = Total surface are of tank = 2πr(r + h) unit square

[ 2 x 22/7 x 0.7 (0.7 + 1)]

= 7.48

Therefore,

• 7.48 square meters of the sheet are required.