EXAMPLE 3 Got Gas?

Although in the United States we have traditionally measured the efficiency of cars in miles per gallon (mpg), the rest of the world measures it in liters per 100 km. The conversion between these two measures is more complicated than other conversions because the U.S. measure has distance (mi) in the numerator and quantity of fuel (gal) in the denominator, whereas the other measure has quantity of fuel (L) in the numerator and distance (km) in the denominator. We need to take this difference into account when doing the conversion.

For example, according to the Environmental Protection Agency (EPA), the most efficient gasoline vehicle of all time was the two-passenger 2000 Honda Insight, at 61 mpg on the highway. (This model was discontinued in 2006 due to poor sales!) What is the equivalent in liters per 100 km?