Bag A has 2 white marbles, Bag B contains 2 black marbles, Bag C contains one white marble and one black marble.
He picks a bag RANDOMLY and takes out ONE marble. It is a white marble.
the question
"What is the probability that the reamining marble from the same bag is also white?”
is the same question as:
"What is the probability that the first marble is from Bag A?"
.
end of story.
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