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?

Given: Radius of cylindrical tank, r = 7m

Height of cylindrical tank, h =3m

The figure of the question is:

The total surface area of cylindrical tank, S = 2 π r( h + r) ............(1)

Putting the values of r and h in equation (1), we get,

S = 2 ×(22/7)× 7(7 + 3)

S = 2 × (22/7) × 7(10)

S = 2 × 22× 10

S = 440 m^{2}

The total surface area of the cylinder is 440 m^{2 }

∴ 440 m^{2} of sheet of metal is required.

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