The area of a cylinder is 956m3. If the circular top is halved, what is the new volume?

3 answers

Your question is rather vague.
When you say that the circular top is halved, are you taking half of the diameter or half of the area ?
The radius is halved
(same as diameter halved, anyway ....)

original:
radius r, height h
surface area = 2πrh + 2πr^2
= 956

πrh + πr^2 = 478
h = (478-πr^2)/(πr)

for new cylinder, height = h, radius = r/2

volume = π(r^2/4)(478-πr^2)/(πr)
= (478r - πr^3)/4

so the relationship depends on the value of r

Are you sure the area was 956 and not the volume?
then the volume would simply be 1/4 of the original, or 239 m^3