Q30 of 47 Page 1

A solid metallic cylinder of diameter 12 cm and height 15 cm is melted and recast into toys each in the shape of a cone of radius 3 cm and height 9 cm. Find the number of toys so formed.

Given:

Cylinder diameter(D) = 12 cm


Cylinder Radius(R) = 6 cm


Cylinder Height(H) = 15 cm


Cone radius(r) = 3 cm


Cone height(h) = 9 cm


Volume of Cylinder = πR2H


⇒ Volume of Cylinder = π × 62 × 15 = 540 π cm3


Volume of Cone =


⇒ Volume of Cone = = 27 π cm3


Number of toys formed =


Number of toys formed =


Answer: The number of toys formed = 20


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