Here is a new poser in measuring liquids that will be found interesting.
A man has two ten-quart vessels full of wine, and a five-quart and a
four-quart measure. He wants to put exactly three quarts into each of
the two measures. How is he to do it? And how many manipulations
(pourings from one vessel to another) do you require? Of course, waste
of wine, tilting, and other tricks are not allowed.