A metallic sphere of radius 10.5 cm is melted and thus recast into small cones, each of radius 3.5 cm and height 3 cm. Find how many cones are obtained.

Volume of a sphere = (4/3)πr^{3}

Volume of a cone = (1/3)πr^{2}h

Given, metallic sphere of radius 10.5 cm is melted and thus recast into small cones, each of radius 3.5 cm and height 3 cm.

Let the number of cones be ‘n’.

⇒ n × (1/3)π × 3.5^{2} × 3 = (4/3) × π × 10.5^{3}

⇒ n = 126

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