The cost of filling a car fuel tank is $45, and this can take you 500 miles before refilling. Mallory was going to her grammy's house, 2000 miles away. If she used 3/5 times as much money on food as she spent on filling the car fuel tank for the whole journey, calculate the total amount of money she used.
Please reason step by step, and put your final answer within \boxed{}.
user