Can Moon make you mad! C(18, 17-r) = ?

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rakeen
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Can Moon make you mad! C(18, 17-r) = ?

Unread post by rakeen » Sun May 22, 2011 10:00 am

I've made a problem. Lets see if you can solve it.
Make a committee of $r$ members from $18$ people where Moon is on that committee. Find, C(18, 17-r)

Need Crux?
think of some identity


Still stuck?
remember summation identity!
r@k€€/|/

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