Puzzles
Cross diagonal cover problem
Source: Gaurish Korpal
Draw with an \(m\times n\) rectangle, split into unit squares. Starting in the top left corner, move at 45° across
the rectangle. When you reach the side, bounce off. Continue until you reach another corner of the rectangle:
![](javascript:showlimage("cross_p1.png"))
![](javascript:showlimage("cross_p2.png"))
![](javascript:showlimage("cross_p3.png"))
![](javascript:showlimage("cross_p4.png"))
![](javascript:showlimage("cross_p5.png"))
![](javascript:showlimage("cross_pend.png"))
How many squares will be coloured in when the process ends?
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puzzles about geometry, or a random puzzle.