AoPS Wiki talk:Problem of the Day/July 15, 2011

Revision as of 12:29, 20 June 2012 by Zua (talk | contribs) (Corrected arithmetic error: C(10,6) = 210, not 270.)
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AoPSWiki:Problem of the Day/July 15, 2011


There are $\binom{10}{6}+\binom{10}{7}+\binom{10}{8}+\binom{10}{9}+\binom{10}{10}$ ways to satisfy the baby storks, out of a total of $2^{10}$ ways to catch the fish. Using the fact that $\binom{n}{k}=\binom{n}{n-k}$, we can quickly evaluate the probability as $\frac{210+120+45+10+1}{1024}=\frac{386}{1024}=\boxed{\frac{193}{512}}$.

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