Question

Two trucks were driven on a 1,680 kilometer (km) trip. the first truck averaged 14 km per liter of fuel for the trip, and the second averaged 12 km per liter. the second truck used how many more liters of gas than the first?

Answer 1

 for the first truck  1680  / 14 = 120 liters used 

the second  1680 / 12 = 140 litres used 

so 140-120 = 20 liters the second truck used  more