perplexus.info :: Games : Rook Placement

Rook Placement (Posted on 2015-09-21)

We place 41 rooks on a 10 x 10 chessboard. Prove that one can choose five of them that do not attack each other.

*** Two rooks "attack" each other if they are in the same row or column of the chessboard.

Source: A problem appearing in Colorado Mathematical Olympiad.

See The Solution Submitted by K Sengupta

Rating: 5.0000 (1 votes)

Comments: ( Back to comment list | You must be logged in to post comments.)

re(2): the “official” solution - spoiler

Comment 5 of 5 |

(In reply to re: the “official” solution - spoiler by Steve Herman)

Elementary, dear Watson.

Posted by Ady TZIDON on 2015-09-27 06:41:47

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