You just moved into a new apartment building, and you are about to mail your first month's rent. You walk down the hallway and notice that there are three different mail chutes. A sign above reads, “Only one of these is actually a mail chute. The other two go to the Dumpster in the back alley.” Naturally, you don't want to send your rent check to the Dumpster. How can you determine the correct chute with a minimum of trips up and down the stairs?
Call the landlord, ask them why they have such a stupid setup, and why they haven't properly labeled the chutes, and then tell them that if they're interested in getting their money, that they had better tell you which chute is the mail chute.
Hmmmmm. What floor are you on? On what floor does the mail chute stop? Uhhmmmmm, go down the stairs to the first floor and out to the back alley to see how the dumpster is positioned to match the 2 chutes. Go back up stairs and pick the other chute, which should be the one on either end, not the one in the middle.
Take 3 envelopes, mark them with 3 different colors and remember which color and chute was for the mailbox. Go down to the dumpster to see which 2 went there. Of course since you remembered the color for the mailbox, if it is not in the dumpster then that chute is the mail chute!
Well done guys Correct Answer Get three pieces of paper and put a unique mark on each of them. Drop one in each chute and then go look in the Dumpster. The piece of paper that is missing went into the outgoing mail. Drop your rent check down that chute.