Answer:
approximately 598.4
Explanation:
Instead of trying to remember when to multiply and when to divide to solve percent problems, I use the following proportion:

450 is = "is", 75.2 = percent of what number = "of" (unknown), so
becomes
.
Solve the proportion:

450(100) = 75.2x
45000 = 75.2x
45000/75.2 = x
x ≈ 598.4