Q2 of 35 Page 202

The base radius and height of a solid metal cylinder are 12 centimetres and 20 centimetres. By melting it and recasting, how many cones of base radius 4 centimetres and height 5 centimetres can be made?

For the cylinder:

Radius of base = 12 cm


Height = 20 cm


Volume of the cone =



= 4 × 12 × 20 π


= 2880π cm3


For the cone:


Radius of base = rb = 4 cm


Height = h = 5 cm







= 108


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