I am heavier when you empty me, and lighter when you fill me. I have no mass of my own to speak of, yet I dictate the weight of everything I hold. What am I?
A balloon
An uninflated balloon weighs slightly less than a fully inflated one filled with air or helium (due to displacement or the compressed air inside). However, if you compare a balloon filled with helium to an empty one, the helium makes it lighter in net weight or buoyant.
About this riddle
Logic riddles give you a few facts and ask what must be true. List what you know, cross out what cannot be, and see what is left.
Difficulty: Easy. More like this: Logic riddles with answers or try Einstein's Logic Grid for a different kind of puzzle.
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