There is no number I can think of that would make the statement untrue.
The result of this when you subtract 83x from both sides leaves you with P = Q.
Unless you know differently, the equation says that P must equal Q no matter what x is. If there is such a condition, it is not obvious.
Answer:
The volume would be 3,421.19m
It's simple multiplication
Volume = w * 2w * 3w = 6w^3 cubic units
About three times. Just divide 74 by 20 which is 3 but exactly it is 3.7.
hoped it helped