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Question
25 circular plates each of radius 10.5cm and thickness 1.6cm are placed one above the other to form a solid circular cylinder. Find the curved surface area and volume of cylinder so formed?
Solution
Given that 25 circular plates each with radius (r) = 10.5cm
Thickness = 1.6cm
Since plates are placed one above other so its height becomes =1.6 X 25 = 40cm
Volume of cylinder = πr2h
= π(10.5)2 x 40
= 13860cm3
Curved surface area of a cylinder = 2πrh
= 2 x π x 10.5 x 40
=2 x 22/7 x 10.5 x 40
=2640cm2
∴Volume of cylinder= 13860cm3
Curved surface area of a cylinder = 2640cm2
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