Question

If the radius of the base and the height of a right circular cone are doubled, then its volume becomes:

• A. 2 times
• B. 3 times
• C. 4 times
• D. 8 times
• E. 9 times

Answer 1

The correct option is D

8 times

Let the original radius and height of the cone be `r' and `h' respectively.

Then, new radius = 2r. New height = 2h.

$\therefore$$\frac{NewVolume}{OriginalVolume}=$$\frac{\frac{1}{3}\times \pi \times {\left(2r\right)}^2\times 2h}{\frac{1}{3}\times \pi \times r{}^2\times h}=\frac{8}{1}$