You need to get gasoline for your car. You can drive ten miles (round trip) to a gas station on the outskirts of town and save 12 cents per gallon on the price of gasoline. If gasoline costs $3.4 per gallon and your car gets 31 miles per gallon for in-town driving, how many gallons of gasoline must you buy at the edge-of-town station to save enough on your fill up to pay for the cost to going to the station and back? Ignore the wear-and-tear cost of operating your car in this example. (Enter your answer as a number without the units of gallons.)