<PRE><B>Question 509183</B>
A bag contains 13 marbles: 6 red ones, 4 blue ones, and 3 yellow ones. 
Suppose that two marbles are selected without replacement.
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(a) What is the probability that a red marble, and then a yellow marble (in that order) are selected?
There are 13*12 = 156 ordered pairs to select.
6*4 = 24 of them are red then blue
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P(red then blue) = 24/156
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(b) What is the probability that neither of the two marbles is blue?
There are 156 pairs
9*8 = 72 of them contain no blue
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P(no blue) = 72/156
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Cheers,
Stan H.
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