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Question
A certain number of metallic cones, each of radius 2 cm and height 3 cm are melted and recast into a solid sphere of radius 6 cm. Find the number of cones.
Solution
Let the number of cones be n.
Let the radius of the sphere be rs =6 cm
Radius of a cone be rc =2 cm
And the height of the cone be h =3 cm
A volume of sphere = n(Volume of a metallic cone)
`=> 4/3 pir_s^3 = n(1/3 pir_c^2 h)`
n = 72
Hence, the number of cones is 72.
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