SOLUTION: Six students (four juniors and two seniors) must be split into three pairs. If the pairs are chosen randomly, what is the probability that the two seniors form one pair? Express yo

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Question 826894: Six students (four juniors and two seniors) must be split into three pairs. If the pairs are chosen randomly, what is the probability that the two seniors form one pair? Express your answer as a common fraction.
I was told the answer to this is 1/5. I also found this question on your website - Question 316800 and answer there is also 1/5. I don't understand how. I get 1/15.
Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website!
Six students (four juniors and two seniors) must be split into three pairs. If the pairs are chosen randomly, what is the probability that the two seniors form one pair? Express your answer as a common fraction.
I was told the answer to this is 1/5.
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# of pairs = 6C2 = 6*5/2 = 15
# of senior pairs: 2C2 = 1
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# of ways to place the senior pair:: 3
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P(one of the 3 pairs is the senior pair) = 3*(1/15) = 3/15 = 1/5
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Cheers,
Stan H.
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