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[SPOILER for 4 - "Monkey beans"] The answer is not probabilistic (that is, the last bean is either white with 100% probability, or black with 100% probability)
by JoachimSchipper 16y ago
[SPOILER for 4 - "Monkey beans"]
The answer is not probabilistic (that is, the last bean is either white with 100% probability, or black with 100% probability). This took me a while to figure out.
- djhworld 16y agoI'm confused at the first hurdle What if the money picks out 2 white beans at the start? "If they are the same he puts a black bean back in the urn"
- jws 16y agoI think the sentence's grammar is awkward. That pile next to the monkey has both black and white beans in it.
- djhworld 16y agoAh I see, this is what confused me, there's no stipulation as to what beans are sitting next to him in a pile.
- JoachimSchipper 16y agoThe monkey randomly picks two beans from the urn, then puts one (from the pile) back. That is, if the monkey picks two white beans from the urn, he gets a black bean from a pile of beans next to him, and puts that black bean in the urn.
- hasha 16y agoI 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 16y agoThat'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"?