Q11 of 70 Page 20

Find the lateral curved surface area of a cylindrical petrol storage tank that is 4.3 m in diameter and 4.5 m high. How much steel was actually used, if of steel actually used was wasted in making the closed tank?


Given,


Diameter of cylindrical tank = 4.3 m


Radius of tank =


Height of tank = 4.5 m


Lateral curved surface area of tank = 2πrh =m2


Let total steel used in making of tank = X m2


Wasted steel = m2


Actual steel used = X-2


∴


=


= x =


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