A cylinder of radius 12 cm contains water to a depth of 20 cm. A spherical iron ball is dropped into the cylinder and thus the level of water is raised by 6.75 cm. Find the radius of the ball (Use π= 22/7)

Volume of a sphere = (4/3)πr^{3}

Volume of a cylinder = πr^{2}h

Given, a cylindrical tub of radius 12 cm contains water to a depth of 20 cm. A spherical iron ball is dropped into the cylinder and thus the level of water is raised by 6.75 cm.

Volume of water displaced = Volume of the iron ball

⇒ r^{3} = 729

⇒ r = 9 cm

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