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प्रश्न
A metallic cylinder of radius 8 cm and height 2 cm is melted and converted into a right circular cone of height 6 cm. The radius of the base of this cone is
विकल्प
4 cm
5 cm
6 cm
8 cm
उत्तर
8 cm
Radius of the cylinder = 8 cm
Height of the cylinder = 2 cm
Height of the cone = 6 cm
Volume of the cylinder = Volume of the cone
Therefore,
`pixx8xx8xx2xx=1/3pixx"r"^2xx6`
`=>128 = "r"^2xx2`
`=> "r"^2 = 128/2`
`=> "r"^2 = 128/2 `
`=> "r"^2 = 64`
`=> "r" = 8 "cm"`
Hence, the radius of the base of the cone is 8 cm.
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