If a car can travel 180 miles on 12 gallons, what is its unit rate?
15 miles per gallon (15 mpg)
In general unit rate for cars are expressed as gallon fuel used per 100 miles. If you want to express this rate, 6.67 gallons of fuel (oil) is necessary to take 100 miles.
If you want to express mileage taken by one gallon of fuel (oil), you need to do the following computation: