Q19 of 49 Page 1

A wooden toy was made by scooping out a hemisphere of same radius from each end of a solid cylinder. If the height of the cylinder is 10 cm, and its base is of radius 3.5 cm, find the volume of wood in the toy. [use π = (22/7)]

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Given-


Radius of Hemisphere(r) = Radius of Cylinder(r) = 3.5 cm


Height of Cylinder(h) = 10 cm


Volume of Cylinder = π × (r)2× h = (22/7) × (3.5)2× 10


= 385 cm3


Volume of Each Hemisphere = (2/3) × π × (r)3


= (2/3) × (22/7)× (3.5)3


= 89.83 cm3


Thus, Volume of wood used in the toy


= Volume of Cylinder-2 × Volume of Each Hemisphere


= 385-2× 89.83


= 385-179.66


= 205.34 cm3


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