Question

Find the total surface area of a closed cylindrical petrol storage tank whose diameter 4.2 m and height 4.5 m.

Answer 1

Diameter of the cylindrical tank ‘d’ = 4.2m 

Thus its radius, r = d/2 = 4.2/2 = 2.1 m

Height of the tank, h = 4.5 m

T.S.A. of the tank = 2πr (r + h)

= 2 × 22/7 × 2.1 (2.1 + 4.5)

= 2 × 22 × 0.3 × 6.6 = 87.12m²