A Consumer Reports survey found that over half of respondents would consider using an alternative-power vehicle such as a hybrid, and 81% said they’d be willing to pay more for a vehicle that lowered their fuel costs. But how much more?

In this lesson students will explore the mathematics of hybrid cars, and in particular how much drivers can expect to save in fuel costs. How long would you have to own a hybrid to justify the extra cost, and is it worth buying one?

Students will

  • Given number of miles a driver travels and fuel economy for different cars (mpg), calculate total gallons used
  • Given the price of a gallon of gas, calculate total fuel cost
  • Use rates or equation solving strategies to determine how long driver would need to own hybrid to justify cost
  • Understand how adjusting variables – e.g. changing fuel price or miles driven – affects total cost of ownership

Before you begin

Students should be able to use unit rates to solve problems involving proportions. For instance, if a driver drives 15,000 miles in a car that gets 50 miles per gallon, students should know that this will require 15,000 ÷ 50 = 300 gallons of gas.

Common Core Standards

Content Standards
Mathematical Practices


Honda, Heather Peters