perplexus.info :: General : Two rights out of 24 wrongs

Two rights out of 24 wrongs (Posted on 2005-07-27)

At a party, my wife set 24 place cards on our round table, but everybody sat down randomly, and nobody was in the right place.

My wife commented: "let's turn the table round, until at least two will be in the right place."

Can this always be so, or was it just a fluke?

Submitted by e.g.

Rating: 3.3000 (10 votes)

Solution: (Hide)

Imagine you turn the table round, a place at the time. (After 24 moves, the table would be back at the original position, so you will move it 23 times.) At some time or other, everybody will be in its place, so there will be 24 coincidences. But, since at the original position there were none, the 24 coincidences will happen as the table is turned 23 times... SOME time there will have to be at least 2 coincidences.

Comments: ( You must be logged in to post comments.)

Subject	Author	Date
Puzzle Thoughts	K Sengupta	2023-03-27 09:15:18
Even if one was right...	Tristan	2005-08-10 04:04:40
re: Comparing proofs	Paul	2005-07-29 21:25:42
re: fluke	McWorter	2005-07-29 17:12:10
fluke	punchmancan	2005-07-29 09:18:31
Comparing proofs	McWorter	2005-07-27 21:22:31
re: Solution	pcbouhid	2005-07-27 15:51:36
Another solution	McWorter	2005-07-27 15:40:54
re: Paul's Solution	Leming	2005-07-27 07:09:01
re: your Solution	Ady TZIDON	2005-07-27 05:35:26
re: Solution	McWorter	2005-07-27 03:05:58
Solution	Paul	2005-07-27 00:54:49

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