

Ask HN: The Case of the Mixed-Up Hats - Errorcod3

There&#x27;s a baseball team that consists of 20 kids. At the end of the season, they all go to the coach&#x27;s house to have a barbecue. The coach says, &quot;You can&#x27;t wear your hats at the barbecue.&quot; So, all the kids take their hats and throw them in a big pile. They fill their little faces with hot dogs and corn on the cob. At the conclusion of the evening, they all reach in at random, grab a hat and put it on their heads.<p>What&#x27;s the probability that 19 out of 20 of these kids get their correct hat?
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tlb
Zero, there's no permutation where only one kid has the wrong hat.

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loganu
If 19 get their hat, won't the 20th also? There won't be another hat to get
mixed up with... So... 1/(20!) ? It's been awhile since I've mathed. Could be
way off. Is this your homework?

