A solid right circular cone of height 60 cm and radius 30 cm is dropped in a right circular cylinder full of water, of height 180 cm and radius 60 cm. Find the volume of water left in the cylinder, in cubic metres.

Height of a cone = 60 cm,


Radius of a cone = 30 cm
volume of cone =

Height of cylinder = 180 cm,


Radius of cylinder = 60 cm
Volume of cylinder = πr2h
Volume of the remaining water = volume of cylinder - volume of cone


= π × 60 × 60 × 180 – × π × 30 × 30 × 60


= 648000π – 1800π (Taking 1800 as common)


= 18000(36π-π)


= 18000 x 35 x = 1.98 m3


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