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Question
A spherical cannon ball, 28 cm in diameter is melted and recast into a right circular conical mould, the base of which is 35 cm in diameter. Find the height of the cone, correct to one place of decimal.
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Solution
Let h be the height of conee. Then
`1/3 π (35/2)^2 h = 4/3 π (14)^3` ....(Because the volume of conical mould is the same as that of the spherical cannon ball.)
⇒ h = `( 4 xx 14 xx 14 xx 14 xx 2 xx 2)/( 35 xx 35)`
⇒ h = `896/25`
⇒ h = 35.84 cm.
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