First, we need to find out just how many miles per gallon this car has.
470 / 20 = 23.5
So our MPG is 23.5.
Then, we just multiply the new amount by our MPG.
75 * 23.5 = 1762.5
So, on 75 gallons, the car could travel 1762 1/2 miles.
Hope that helped! =)