Question
The curved surface area of a right cylinder is 3696
cm³. Its height is three times its radius. What is the capacity (in litres) of the cylinder? (Take π = 22/7)Solution
Let the radius of the cylinder be ‘r’ and the height of the cylinder be ‘h’. Curved surface area of cylinder = 2πrh ⇒ 2πrh = 3696 ⇒ 2πr × 3r = 3696 (h = 3r) ⇒ r^2 = (3696 × 7)/(22 × 6) ⇒ r^2 = 196 ⇒ r = 14 cm ⇒ h = 3r = 3 × 14 = 42 cm Volume of cylinder = πr^2h ⇒ (22/7) × 14 × 14 × 42 ⇒ 25872 cm We know, 1 cm = 0.001 litre ⇒ 25872 × 0.001 ⇒ 25.872 litres
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