Environmental Protection Agency: Miles Per Gallon (MPG) Math

Buying a high MPG vehicle saves you money at the pump.

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“Less carbon pollution, too!”

  • Annual Fuel Cost of $2,625 at 20 MPG
  • Annual Fuel Cost of $1,050 at 50 MPG

Assumes 15,000 miles per year and $3.50 per gallon.

But what if my MPG varies?

Let’s compare how much fuel two cars use over a year.

  • 20 MPG to 19 MPG (750 gallons to 789 gallons)
  • 50 MPG to 49 MPG (300 gallons to 306 gallons)

A loss of 1 MPG costs:

  • 39 gallons and $138 for the 20 MPG car
  • 6 gallons and $21 for the 50 MPG car
  • Losing 1 MPG on the 20 MPG car costs more than losing 1 MPG on the 50 MPG car.

Even a loss of 5 MPG at 50 costs you less than 1 at 20.

  • “Yep! That’s 33 gallons and $117.”

Small differences in calculated gallons and cost may occur due to rounding.

Though MPG varies, Higher MPG always saves fuel and carbon!!

Science Topics
Atmospheric Sciences, Fossil Fuels, Pollution
Middle School, High School, College
6th Grade, 7th Grade, 8th Grade, 9th Grade, 10th Grade, 11th Grade, 12th Grade, College, Adults

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