Q7 of 52 Page 160

A cylindrical bucket of diameter 28 cm and height 20 cm was full of sand. When the sand in the bucket was poured on the ground, the sand got converted into a shape of a cone. If the height of the cone was 14 cm, what was the base area of the cone?

Diameter of cylinder = 28 cm


⇒ Radius of cylinder, R = 14 cm


Height of cylinder, H = 20 cm


Volume of cylinder, VC = πR2H



Height of cone, h = 14 cm


Radius of cone = r



Now, as the sand in cylinder forms the cone,


⇒ V = v





⇒ r = 28.98 cm


Base area = πr2



⇒ Base area = 2640 sq. cm


∴ The base area of the cone formed is 2640 sq. cm


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