Pria bought a new car that advertised an estimated gas mileage of 35 miles per gallon. The car has a 12-gallon tank. She filled her car full of gas and was able to drive a total of 372 miles. What was the difference, in miles per gallon, between Pria's mileage and the advertised mileage?
Pria's car achieved a rate of 372 miles / 12 gallons = <<372/12=31>>31 miles per gallon.
Therefore, it was a difference of 35 - 31 = <<35-31=4>>4 miles per gallon.
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