Q44 of 107 Page 16

The surface area of a solid metallic sphere is 616 cm2. It is melted and recast into a cone of height 28 cm. Find the diameter of the base of the cone so formed .

Surface area of the sphere


⇒ 4πr2 = 616




⇒ r2 = 49


⇒ r = √49


⇒ r = 7 cm


Diameter of base = 7 × 2


= 14 cm


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