A company manufactures hollow spherical basketballs with an internal radius of 12 cm. If the thickness of the rubber is 0.5 cm, what is the volume of rubber used in making one basketball?
(Use π=22/7)
Show answer & explanation
Correct answer: B
Explanation
Inner radius r = 12 cm
Thickness of rubber = 0.5 cm
Therefore, outer radius R = 12 + 0.5 = 12.5 cm
Volume of rubber = Volume of outer sphere − Volume of inner sphere
= 4/3 × π × (R³ - r³)
= 4/3 × 22/7 × (12.5³ - 12³)
= 4/3 × 22/7 × (1953.125 - 1728)
= 4/3 × 22/7 × 225.125
= 943.6 cm³