An
old chestnut goes as follows:
There are three houses and three utilities, like so:
H1 H2 H3
U1 U2 U3
How can you connect each house to each utility, by drawing lines without crossing? (Pretend this is on a sheet of paper; you can't cross around to the back of the paper, make holes in the paper, or run utility lines through the houses or other utilities.
Answer