Austin Warby edited How_many_ways_can_we__.tex  over 8 years ago

Commit id: 1e369ea5528e1a9ed0e50077d6c65f05d41e64af

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_ \ _ \ _ \ _ \ _ \ _ \ _ \ _ \ _ \\  Simply put all we are deciding in each case is where to put the bars. Therefore we have 9 slots choose 2 slots to place the bars or $\binom {9}{2}$. Equivelantly, we also have 9 slots choose 7 slots to place the stars or $\binom {9}{7}$. Feel free to verify that those are indeed the same. \\  To finish the problem $\binom{9}{2}= \frac{9!}{2!(7-2)!}=36$ \frac{9!}{2!(9-2)!}=36$  different ways to place the candies.