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

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 = (478πr^2)/(πr)
for new cylinder, height = h, radius = r/2
volume = π(r^2/4)(478πr^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