Comments on: a riddle: hats

By: Jeff

Jeff — Sat, 12 Mar 2005 04:55:52 +0000

Hehe, yep, this is really Andrew’s idea… I figured I’d see if any non-mathy folks could figure it out.

By: Andrew

Andrew — Sat, 12 Mar 2005 02:20:45 +0000

That is quite an interesting problem. Wherever did you hear of it? Surely it sprung from a true fountain of knowledge.

By: Jeff

Jeff — Wed, 09 Mar 2005 19:37:29 +0000

Yes, that is correct. Interestingly enough, it does not matter how many people are at the party; on average exactly one person will get their hat back.

Even more interesting is the fact that regardless of what order they go in, each person has an identical chance of getting his or her hat back: 1 in n.

By: ian

ian — Wed, 09 Mar 2005 17:19:09 +0000

well, after running about 10000 sims for a 20-person party, i found that one person got their own hat on average. i could maybe actually figure out a general solution, but i’d first be interested to see if that answer is correct.

and now, i have to go pay those 20 people for going to 10000 parties with pissed-off hat-checkers

By: Jeff

Jeff — Wed, 09 Mar 2005 00:17:19 +0000

Perhaps he is forced to eat his own hat.

By: Mom

Mom — Tue, 08 Mar 2005 12:51:20 +0000

3. They might think it’s a new game of hat roulette and the one who gets his own hat is forever banned from the group.

By: Mom

Mom — Tue, 08 Mar 2005 12:37:12 +0000

As a non-math person I have two answers:
1. They were all drunk and didn’t care what hats they got.
2. They thought it was the new “in” game to trade hats, and this started a trend.