Question 159379
There are six people, six seats. What is the probability that both the youngest girl and the eldest boy (3 girls, 3 boys in total) are seated at each end?
(yes, this one is easy...but the next question i don't get at all...)
# of ways to place the youngest and eldest as described: 2
# of ways to arrange the remaining 4: 4!  24
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Total # of ways to get the pattern you want: 2*24 = 48
Total # of ways to arrange the 6 with no restrictions: 6! = 720
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Probability of succeeding : 48/720 = 0.066667
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What is the probability that exactly one of them (not at least, but exactly one of them) gets seated at the end? 
# of ways to get one of them on the end: 2*2 = 4
# of ways to place the one not on the end: 4
# of ways to place the remaining 4: 4! = 24
Total # of ways to succeed: 4*4*24 = 96
Total # of ways to arrange the 6 with no restrictions: 72
Probability of succeeding: 96/720 = 0.133333..
Cheers,
Stan H.
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# of ways