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Figure 1 | | |
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Figure 2
In the first diagram nine lines have been drawn, equally spaced up and down and left to right, to make 20 squares (12 of side 1, 6 of side 2, and 2 of side 3), whereas in the second diagram we have more lines, ten, but with fewer squares, 17. This puzzle is to make exactly 100 squares using the fewest lines.
Cinelli