87 octane gasoline, often called "regular" gas, is one of the most commonly used fuels in the United States. But what gives it that 87 rating is a word you've probably heard a time or two: Ethanol.

DENVER (KDVR) — Gas prices are fluctuating across the country, and a few states offer a “cheaper” octane option that isn’t found in most places. It has to do with the altitude. Most states have the ...

CINCINNATI — As gas prices move back up to $4 a gallon, closing in on $5 in California, some drivers are once again checking out a cheaper option: Ethanol based gas, or "Flex Fuel." You might have ...

Add Yahoo as a preferred source to see more of our stories on Google. DENVER (KDVR) — Gas prices are fluctuating across the country, and a few states offer a “cheaper” octane option that isn’t found ...