1 gallon is 4 quarts or 8 pints. 9 gallons - 3 gallons= 6 gallons Then convert it to quarts so, 6×4=24 quarts. Then subtract that by 10 quarts so, 24-10=14 quarts. Because you requested the number in pints, you have to convert it again and because there are 2 pints in a quart you multiply it by 2 so, 14×2=28 pints left over.