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How could you arrange 36 trees into 9 rows of 8? (Note that a row is a straight line that can go in any direction.)

Deusovi
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Aaron
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1 Answers1

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Draw nine lines so that no two are parallel and no three meet in the same place, then place a tree at each intersection point. Every pair of lines intersects, so there are $\binom{9}{2}=36$ trees, each row being one of the nine lines.

Illustration:

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Mike Earnest
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