Question

A metallic sphere of radius 21cm is melted and recast into small cones of radius 7cm and height 6cm. Find the number of cones obtained.

Answer 1

Step-by-step explanation:-

Diameter of sphere = 21 cm Radius = 21/2 cm Height of the cone = 3 cm Radius of the cone = 7/4 cm Volume of the sphere = 4/3 πr3 = 4/3 x π x (21/2)3 cm3 Volume of cone = 1/3 πr2 h = 1/3 π (7/4)2 x 3 cm3 Let n be the number of cone formed, then n = (Volume of the sphere) / (Volume of cone) n = (4/3 x π x (21/2)3) / (1/3 π (7/4)2 x 3) = 504