Fill the 3 gallon jug first. Pour the 3 gallons into the 5 gallon jug. Fill the 3 gallon jug again. Fill up the 5 gallon jug with the 3 gallon jug. You will have 1 gallon remaining in the 3 gallon jug. Pour out the 5 gallon jug. Pour the remaining spiced cider from the 3 gallon jug to the 5 gallon jug. Fill the 3 gallon jug again. Pour into the 5 gallon jug. You will have 4 gallons!
