Marble Garble (Hint: It's not obvious)
Probability
Level
3
You have 3 bags, each containing 2 marbles. Bag A contains 2 white marbles, Bag B contains 2 black marbles, and Bag C contains 1 white marble and 1 black marble.You pick a random bag and it is a white marble. What is the probability that the remaining marble from the same bag is also white?
1/3
2/3
1/2
3/5
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1 solution
We will eliminate bag C because that doesn't have a single white marble. It can be: Bag A, first white marble. The other marble will be white. Bag A, second white marble. The other marble will be white. Bag C, the white marble. The other marble will be black. That is 2 whites and 1 black. Marble, not bags.