Q5 of 70 Page 20

A solid cylinder has total surface area of 462 cm2. Its curved surface area is one third of its total surface area. Find the radius and height of the cylinder.


Given,


Total surface area of cylinder = 462 cm2


Curved surface area = (total surface area)


=


= 2πrh = 154


= h =


And,


=


=


=


= 2r2 = 98


= r = 7


So, radius of cylinder = 7 cm


∴ height =


2πrh = 154


=


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