A cylindrical tub of radius 12 cm contains water to a depth of 20 cm. A spherical form ball is dropped into the tub and thus the level of water is raised by 6.75 cm. What is the radius of the ball?

Volume of a sphere = (4/3)πr^{3}

Volume of a cylinder = πr^{2}h

Volume of water displaced = Volume of the iron ball

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

⇒ r^{3} = 729

⇒ r = 9 cm

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