SOLUTION: From 9 mathematicians and 6 physicists a committee of 4 mathematicians and 3 physicists is to be formed.What is the probability that commitee has a) 3 particular mathematicians b

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Question 91194: From 9 mathematicians and 6 physicists a committee of 4 mathematicians and 3 physicists is to be formed.What is the probability that commitee has
a) 3 particular mathematicians b)one particular physicist
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
From 9 mathematicians and 6 physicists a committee of 4 mathematicians and 3 physicists is to be formed.What is the probability that commitee has
a) 3 particular mathematicians b)one particular physicist
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Mathematicians:
I'm going to assume the selector knows which 9 are mathematicians and
which 6 are physicists. If he/she doesn't the problem is quite different.
---------------
Pick the special three then pick one more to get four:
P(pick the three) = 1/9C3 = 1/64
P(pick one more) = 6/6 = 1
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Physicists:
Pick the special one then pick two others:
P(pick the special one) = 1/6
P(pick 2 others) = (5/5)(4/4)=1
============================
Prob(the combined event) = 1/64 * 1/6 = 1/504 = 0.00198...
===============================
Let me know if this is the answer you have and/or whether
my assumption is wrong. If you have another solution I
would like to see it.
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Cheers,
Stan H.