SOLUTION: I am having a hard time with this one. Can someone please help me?? A box contains blue chips and red chips. A person selects two chips without replacement. If the probability of

Question 133739: I am having a hard time with this one. Can someone please help me??
A box contains blue chips and red chips. A person selects two chips without replacement. If the probability of selecting a blue chip and a red chip is 32/128, and the probability of selecting a blue chip on the first draw is 5/16, find the probability of selecting the red chip on the second draw, given the first chip selected was a blue chip.
Answer by stanbon(48568) (Show Source):
You can put this solution on YOUR website!
A box contains blue chips and red chips. A person selects two chips without replacement. If the probability of selecting a blue chip and a red chip is 32/128, and the probability of selecting a blue chip on the first draw is 5/16, find the probability of selecting the red chip on the second draw, given the first chip selected was a blue chip.
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That is a "conditional" problem.
P(red on 2nd | blue on 1st) = [P(red on 2nd AND blue on 1st)]/[P(blue on 1st)]
= (32/128)/(5/16) = 0.25/0.3125 = 0.8 = 4/5
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Cheers,
Stan H.