Here is another classic example of the three jug problem posed in the Mathigon Puzzle Calendars for 2017.
“How can I measure exactly 8 liters of water, using just one 11 liter and one 6 liter bucket?”
It is assumed you have unlimited access to water (the “third jug” of at least 17 liters). You can only fill or empty the jugs, unless in poring from one jug to another you fill the receiving jug before emptying the poring jug. (Hint: see the Three Jugs Problem.)
See Two More Jugs.