Photo:
THE MIRROR
Chess without pieces is no fun.
But a chessboard is an ideal stage for puzzles.
However, Nancy and Noah have two unusual chess boards.
Instead of the usual 8x8 fields, they only consist of 7x7 fields.
Both want to completely cover their board with 2x1 dominoes.
Only one field should remain free - there is already a gray chip there.
Nancy gets the left board, Noah the right.
Who finishes faster?
noah
wins
He has plenty of time to find a solution.
Because
Nancy
will not be able to completely cover her board.
There is no solution for her board.
The two must cover 7x7 - 1 = 48 squares.
For this they need 24 dominoes each.
But there is a problem with Nancy's board.
The 7x7 board consists of 25 white and 24 black squares.
The gray chip lies with her on a black field.
So she has to cover 25 white and 23 black squares with 24 dominoes.
This is impossible because a domino always occupies a white and a black square on the chessboard.
It's different with Noah.
The gray chip is on a white field.
He must then cover 24 white and 24 black squares.
And there are actually solutions that are easy to find.
I discovered this riddle in Pierre Berloquin's book »Headnuts«.
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