One type of recreational math problem is to find a minimum number of chess pieces of the given kind and place them on a chess board in such a way, that all free squares of the board are attacked by at least one piece.

Can you place 5 queens on an 8x8 chessboard so that all the free squares are attacked by at least one queen, and no queen can be attacked by another queen?







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Using the combinations formula, 64C5, there are 7,624,512 possible arrangements of five queens on an 8×8 board.   There are 65 distinct solutions.   Here is one of them:







Now, can you place 5 queens on the board which attack all squares on the board, including occupied ones?



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