A) cost = (cost/gallon)*gallons
.. 83.58 = 3.799*gallons
.. 83.58/3.799 = gallons ≈ 22.001
The SUV has a 22-gallon tank.
B) miles per gallon = miles/gallons
.. miles per gallon = (24297 -24033)/((3/4)*22) = 264/16.5 = 16
The gas mileage for the trip was 16 miles per gallon.