If the radius of a sphere is increased by 10%, then its volume will increase by:
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → 33.1%
The volume of a sphere, \(\frac{4}{3}\pi r^3\), varies as the cube of the radius, so a 10% rise in the radius multiplies the volume by \(1.1^3\), not by 1.1.
New volume \(=1.1^3=1.331\) times the old volume
Increase \(=1.331-1=0.331\), that is, 33.1%