What weighs 50 percent more than a gallon of water but when its weight is reduced by 50 percent weighs less than a gallon of water?

Answer 1

1.5 gallons of water does that.

1.5 gallons weighs 50% more than 1 gallon. If you reduce it 50%, you have 0.75 gallon,

and that weighs less than 1 gallon.

Answer 2

A gallon of water weighs about 8.3 pounds. The answer is ice. Ice weighs around 12.45 pounds, which is 50% more than a gallon of water, but when it melts and its weight is reduced by 50%, it weighs around 6.225 pounds, which is less than a gallon of water.