SOLUTION: An urn contains 3 red balls and 7 green balls. A ball is drawn randomly and in its place are put 2 of the opposite color. Then another ball is drawn randomly. Find the conditional
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-> SOLUTION: An urn contains 3 red balls and 7 green balls. A ball is drawn randomly and in its place are put 2 of the opposite color. Then another ball is drawn randomly. Find the conditional
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Question 1026168: An urn contains 3 red balls and 7 green balls. A ball is drawn randomly and in its place are put 2 of the opposite color. Then another ball is drawn randomly. Find the conditional probability that the first ball was green given that the second ball is red. Answer by robertb(5830) (Show Source):
You can put this solution on YOUR website! We have to find P(G1|R2) = P(G1 ∩ R2)/P(R2).
By the law of total probability,
P(R2) = P(G1 ∩ R2)+P(R1 ∩ R2) = P(R2|G1)P(G1) + P(R2|R1)P(R1)
=
==>P(G1|R2) = P(G1 ∩ R2)/P(R2) = .
