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Mutilated chessboard problem Question
This post describes a classic puzzle.
If you have previously seen this puzzle I request that you allow someone else to solve it and post their answer.
Thank you!
Mutilated chessboard problem:
2 corner squares of a chessboard have been cut out as shown below.
You have 31 dominoes each of which can exactly cover two adjacent squares in the chessboard.
Can you completely cover every square of the mutilated chessboard with the 31 dominoes?
Attribution:
Max Black in his book Critical Thinking (1946)
1 answer
Answer! Click here to reveal
It is not possible to completely cover every square of the mutilated chessboard with the 31 dominoes.
Details! Click here to reveal
Every domino whether placed horizontally or vertically will cover exactly one black square and one red square. So 31 dominoes would cover 31 black squares and 31 red squares.
But the mutilated chessboard has 32 black squares and 30 red squares. Therefore the covering is not possible.
There is a Wikipedia article about this puzzle:

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