If height of a circular cone is decreased by 10% and its radius is increased by 10%, then what will be the change in its volume?
Answer & explanation
Correct answer: option 3
Let the height and the radius of the cone = 10
Now according to the question,
Before After
(Radius)2 100 121
Height 10 9
-------------------------------------
Volume = 1000 1089 = 89 (Change)
%age change = 89 × \(\frac{100}{1000}\) = Increases by 8.9%.