According to Fueleconomy.gov, a gallon of gasoline weighs about 6.3 pounds, therefore 15 gallons of gasoline weighs around 94.5 pounds.
A bit of a trivia, did you know that about 140.43 billion gallons of gasoline were consumed in the United States in 2015, a daily average of about 384.74 million gallons? This was about 1.5% less than the record high of about 390 million gallons per day (or about 9.29 million barrels per day) consumed in 2007.
Learn other facts and view updated U.S. Regular Gasoline Prices per gallon at U.S. Energy Information Administration.
Find the cheapest gasoline prices in your area at Fuel Economy - Local Prices.
Find out how you can save money on gasoline by following Fuel Economy - Gas Mileage Tips.