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SwissPoker
12-10-2005, 07:48 AM
You have 2 boxes with 2 pigeonholes each. Box A has 1 gold coin in each pigeonhole. Box B has 1 silver coin in one pigeonhole and 1 gold coin in the other. Now, you are blindfolded and chose a box and open a pigeonhole to find a gold coin. What are the chances that the other pigeonhole of the same box contains the silver coin? And what are the chances that the other pigeonhole of the same box contains another gold coin?

Thanks for your answer.

mostsmooth
12-10-2005, 10:04 AM
1/3 for silver, 2/3 for gold

AaronBrown
12-10-2005, 12:21 PM
mostsmooth is correct.

In this problem the boxes and the first coin are distractions. You have three pigeonholes, two with gold coins, one with silver. Pick any pigeonhole at random, any way you want, and the chance is 1/3 it will have the silver coin and 2/3 that it will have the gold.