Question
A hollow sphere of external and internal diameters of 10
cm and 6 cm, respectively, is melted and made into another solid in the shape of a right circular cone of base diameter 10 cm. Find the height of the cone.Solution
 The volume of the hollow sphere: = 4/3 π (53-33) =4/3 ×98 π = (392/3) π cm³ Volume of the cone:  = π/3 (52) h = (25/3) πh cm³ 3 Equating volumes: 392/ 3 π = 25/3 πh h= 392/25 h=15.68 cm. The height of the cone is 15.68 cm.
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