How many liters of gasoline would your need to buy to complete a 142-km trip in Europe?

Question

In Europe, gasoline efficiency is measured in km/L. If your cars gas mileage is 20.0 mi/gal, how many liters of gasoline would you need to buy to complete a 142-km trip in Europe?

Answer 1

Hi Kristen L.,

We have mi/gal which we'll need to convert to km/L. I have 1 mi = 1.61 km, and 1 gal = 3.79 L.

Also given is 20 mi = 1 gal ( 20 mpg ).

I like to form conversion problems into the question asked equals what is given; ? L = 142 km, or how many Liters is equal to a 142 km trip? (It's an easy exercise my chemistry teacher taught, and has stuck with me). Then set the equals as fractions making sure dimensions cancel.

? L = 142 km*(1 mi / 1.61 km)*(1 gal/ 20.0 mi)*(3.79 L/ 1 gal) = 16.7 L

I hope this helps, Joe.