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PROJECT EULER · #0783

Urns

Statement only · UnsolvedOriginal problem ↗

Given n and k two positive integers we begin with an urn that contains kn white balls. We then proceed through n turns where on each turn k black balls are added to the urn and then 2k random balls are removed from the urn.

We let Bt(n,k) be the number of black balls that are removed on turn t.

Further define E(n,k) as the expectation of t=1nBt(n,k)2.

You are given E(2,2)=9.6.

Find E(106,10). Round your answer to the nearest whole number.

Write-up coming later

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