H. E. Dudeney, Amusements in Mathematics (1917) No. 347 · Puzzles · Chessboard puzzles

Counting the Rectangles

Can you say correctly just how many squares and other rectangles the chessboard contains? In other words, in how great a number of different ways is it possible to indicate a square or other rectangle enclosed by lines that separate the squares of the board?

~8 minWritten answer · compare with the solution

H. E. Dudeney, Amusements in Mathematics (1917) · No. 347

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