Using Rates to Determine Efficiency

Find Fuel Efficiency

Work Time

Find Fuel Efficiency

Denzel and Jason took different approaches to solving the fuel efficiency problem. Look at each approach and then answer the following questions. Remember to specify the appropriate unit, such as miles per gallon or gallons per mile.

  • What is the unit rate in Denzel’s calculation?
  • What is the unit rate in Jason’s calculation?
  • Who calculated the fuel efficiency correctly?
  • How far could Jason’s dad travel using 16 gallons of gas?
  • Jason’s dad drove the car 150 miles. How much gas did the car use?
  • Which rate—Denzel’s or Jason’s—was most helpful in answering each question?


  • What are the quantities involved in the problem?
  • What operation do you need to use in order to find the rate?
  • In the last lesson, to find the unit price you divided the total price by a quantity. To determine the fuel efficiency of a car, should you divide miles by gallons or gallons by miles?