Hey RedFalcon,
The question is asking you to find the time it's going to take you to get to that place, so that's just normal t=d/s , and if I am not wrong the time is in fact 30 minutes (0.5) and not two hours .Since you are dividing 220 by 440 and then you can multiply that by 9,000. This would give you the correct answer which is 4,500 lbs.
Hope I could help,
N