Answer:
27
Step-by-step explanation:
Suppose that the dimensions of the rectangular prism are L, W and H.
Then the volume is V = L*W*H.
If you mean to increase EACH dimension by a factor of 3, then we' have
V = (3L)*(3W)*(3H), or V = 27 L*W*H.
The volume of the modified prism would be 27 times larger than that of the original prism.