Gold and Silver Puzzle

At first, there was a 1/2 chance of picking from either bag. But when you picked out a gold coin, you got more information about which bag you probably picked from. Since 2 of the 3 gold coins were in the bag with 2 gold coins, there’s a 2 in 3 chance you picked from the bag with 2 gold coins. Therefore, there's a 2 in 3 chance that the other coin in that bag is also gold.

To learn more, read about Conditional Probability

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