In the united states fuel efficiency of cars is measured in miles per gallon units or simply mpg, mpg means how many miles a car can travel using one gallon of fuel. in metric countries fuel efficiency is measured differently: how many liters of fuel a car uses while traveling a distance of 100 kilometers. if the fuel efficiency of your car is 26.9 mpg, then how many liters of fuel does it use on 100 kilometers? (lon-capa uses letter l for liter. possibly useful conversion factors: 1 gallon = 3.785 liters, 1 mile = 1.609 kilometers.)