After Rob has lost, he will have 120 dollars. We can work this out by establishing that if Rob had 280 dollars before the final competition, and the ration at the point was 4 to 7, then this means that Tom must have had 4/7 of what Rob had, so x=4/7 * 280, x = 4 x 40, x = 160. This means that Tom had 160 dollars and Rob had 280. Adding this together they have a combined 440 dollars, but the ratio is now 8:3. There are 11 parts to the ration, due to the fact that 8 and 3 is 11, so we need to work out one part of the ratio - 440 divided by 11 equals forty. This means that Tom has 8 multiplied by 40 (320 dollars) and Rob has 40 multiplied by 3, so 120 dollars.