Here are three puzzles that qualify as truly ancient chestnuts. Every
puzzler that's been around for a while has heard them. But these three
are submitted to the Grey Labyrinth more than any other, so I'd like to
bring them out, show them around, and shoot them dead.
Ancient Chestnut #1:
Three salesmen arrive at a hotel one night and ask for a room. The manager
informs them the price is $30.00. Each gives the manager a ten, and they
retire for the night.
Shortly, the manager remembers that the room was at a discount, on account
of it being haunted. So he tells his bellhop that the room was only $25.00,
gives the bellhop five dollars and tells him to give the men the refund.
The bellhop is slightly crooked and rationalizes, "Five doesn't
divide well among three, I'll save them some arguing and just give them
a dollar each." Which he does, and keeps the leftover two dollars
Now each of the men paid $9.00 for the room, for a total of $27.00. The
bellhop has $2.00. 27+2=29. What happened to the missing dollar?
Ancient Chestnut #2:
In a small town there are three houses: one white, one blue, one green.
There are also three somewhat under utilized utilities: gas, electricity,
and water. Is it possible to connect each house to all three utilities,
so that no connection crosses another? (See diagram, below)
Ancient Chestnut #3:
"There are only three words in the English language ending in 'gry'.
Angry and hungry are two of them. What is the third word? The word is
something that everyone uses every day. If you have listened carefully,
I have already told you what it is."