Q1 of 70 Page 21

Find the volume of a sphere whose radius is :

(i) 2 cm


(ii) 3.5 cm


(iii) 10.5 cm

Volume of a sphere = (4/3)πr3


(i) radius is 2 cm


⇒ Volume of the sphere = (4/3) × (22/7) × 23 = 33.52 cm3


(ii) radius is 3.5 cm


⇒ Volume of the sphere = (4/3) × (22/7) × 3.53 = 179.67 cm3


(iii) radius is 10.5 cm


⇒ Volume of the sphere = (4/3) × (22/7) × (10.5)3 = 4851 cm3


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