Recently I arrived back home from a short trip to Iowa. While there I filled up on gas only one time, but when I did, I saw something that caught my eye. The price. Unleaded 87 $3.47 a gallon Super unleaded 89 $3.31 a gallon 89 cheaper then 87? This was at the same gas station, so that can't be the reason. I did notice that under the 89 it said it contains 10% ethanol, while saying nothing under then 87. I also know that Iowa contains a lot of corn fields. Is the difference in price because the ethanol is cheaper there? Maybe there is a local ethanol plant that can produce it cheaper then importing in gas from a refinery that might be further away. I really have no idea, just guesses, does anyone know why this is the case?