If the length, height, and width of the volume are L, W, and H, respectively. Then the volume would be equal to V = L(W)(H) = LWH.
Given that the length and width have tripled, then the new length and width of the prism would be 3L and 3H. Thus, the volume of the new prism is V = (3L)(3H)(W) = 9LWH.
Comparing this to the original volume, we can clearly see that the volume has increased 9 times after the changes.
Answer: Volume becomes 9 times larger.