If the height of a cone is doubled, then its volume is increased by

Radius $=r$

Height $=h$

Volume, $V=\frac{1}{3}\pi r^{2}h$

If height is doubled, $h^1=2h$

Volume $V^1=\frac{1}{3}\pi r^2{h}^1$

$=\frac{1}{3}\pi r^2\left(2h\right)$

$=2\left(\frac{1}{3}\pi r^{2}h\right)$

$=2v$

Increase in volume $=\frac{V^1-V}{V}\times 100\%$

$=\frac{2V-V}{V}\times 100\%$

$=\frac{V}{V}\times 100\%$

$=100\%$