The volume of a sphere is 144π cm3. If the radius of the sphere is doubled, by what percentage does the volume increase?
Show answer & explanation
Correct answer: A
Explanation
The correct answer is option 1 i.e. 700%.
Sphere volume = (4/3)πr3 where r = radius
New radius = 2r ⇒ New volume = (4/3)π(2r)3
= (4/3)πr3 × 8
= 8 × Old volume
Increase percentage = (8 – 1) × 100 = 700%