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dakka2dakka
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Combinatorics problem

by dakka2dakka Thu Aug 09, 2012 8:47 am

I have a bag with X red balls and Y blue balls.

Balls are withdrawn one by one until the bag is empty, and their order is recorded.

What is the expected number of times two consecutive balls are blue?

Thanks
tim
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Re: Combinatorics problem

by tim Thu Aug 09, 2012 3:21 pm

Before we help with this question, we need you to show some effort of your own. What did you try on this question? Where did you get stuck?
Tim Sanders
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