Question

An american car travels 32 miles on one gallon of gas. A European car travels 12.7 kilometers on one liter of gas. Which car gets better gas mileage? Explain your reasoning.

Answer 1

In order to meaningfully compare the distance per unit of fuel, we need to convert one set of measurements into the same units as the other set of measurements. Doesn't matter if we convert miles per gallon to kilometers per liter or visa versa. So let's convert 32 miles per gallon to kilometers per liter. 32 mile/gal * 1.60934 km/mile / 3.78541 L/gal = 13.60457124 km/L And since 13.6 km/L is better than 12.7 km/L, the American car gets better gas mileage than the European car. To demonstrate that it didn't matter which we converted, let's do the problem again, except this time we'll convert from km/L to miles/gal. So 12.7 km/L / 1.60934 km/mile * 3.78541 L/gal = 29.87231225 mile/gal And once again, 32 mile/gal is higher than 29.9 mile/gal. So the American car still has better gas mileage.