Question 1000283
volume = pi * r^2 * h


your new r = 1/2 * the original r = (1/2 * r).
your new h = 2 * the original h = (2 * h)


formula becomes:


volume = pi * (1/2 * r)^2 * (2 * h) which becomes:


volume = pi * (1/2)^2 * r^2 * 2 * h which becomes:


volume = pi * 1/4 * r^2 * 2 * h which becomes:


volume = pi * 1/4 * 2 * r^2 * h which becomes:


volume = pi * 2/4 * r^2 * h which becomes:


volume = pi * 1/2 * r^2 * h.


the new volume is half the original volume.


here's an example:


assume the radius is equal to 4 and the height is equal to 4.


original volume is pi * 4^2 * 4 = pi * 16 * 4 = pi * 64


revised volume is pi * 2^2 * 8 = pi * 4 * 8 = pi * 32


pi * 32 is 1/2 the volume of pi * 64.