When the numbers represent money, it seems unusual to have the product of two quantities of money (what does it mean?).
If we forget about the dollars and deal with the numbers, we can simplify the arithmetic:
504000/112000-436100*6300/112000=4.5-24530.625=-24,526.125.
If we reinsert the dollars we get 4.5-$24,530.625, which cannot be simplified because we have a pure number and an amount of money. The pure number is not an amount of money.