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प्रश्न
A solid metallic spherical ball of diameter 6 cm is melted and recast into a cone with diameter of the base as 12 cm. The height of the cone is
पर्याय
2 cm
3 cm
6 cm
उत्तर
Clearly,
The volume of recasted cone = volume of sphere
`1/3 pi(12/2)^2 xx h = 4/3 pi (6/3)^3`
`1/3 xx 36 xx h = 4/3 xx 27`
`h = (4 xx 27 xx 3 )/(3 xx 36)`
` h = 3 cm`
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