I don't think so. After each drawing the number of whites is congruent modulo 2 ... | Hacker News

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		hasha on Jan 14, 2011 \| parent \| context \| favorite \| on: Oxford Undergrad CS Admission Interview Problems I don't think so. After each drawing the number of whites is congruent modulo 2 to the initial number of whites. Hence, when there are two beans left, one will be white and the other black so the last bean will be white.

JoachimSchipper on Jan 14, 2011 [–]

That's the right answer, yes (you can even skip "Hence, when there...the other black"); but what do you mean by "I don't think so"?

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