Here is a two player game – there are three piles of stones: one with 10 stones, one with 15 stones, and one with 20 stones. At each turn, a player can choose one of the piles and divide it into two smaller piles. The loser is the one who cannot do this. Who will win and how?
Source: Mathematical Circles, by Dmitri Fomin, Sergey Genkin and Ilia Itenberg
Age Group: For all ages
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