Question 473393: Janice has 8 DVD case on a shelf ,one for each season of her favorite TV show. Her brother accidentally knocks them off the shelf onto the floor .When her brother put them back on thr shelf, he does not pay attention to the season number and put the case back on thr shelf randomly. Find each probability.
P(season 5 in the correct position)
P(season 1 and 8 in the correct positions)
P(season 1 through 4 in the correct positions)
P(all even number seasons followed by all odd numbered seasons)
P(all even number seasons in the correct position)
P(season 5 through 8 in any oder followed by seasons 1 through 4 in any order)
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! Janice has 8 DVD case on a shelf ,one for each season of her favorite TV show. Her brother accidentally knocks them off the shelf onto the floor .When her brother put them back on thr shelf, he does not pay attention to the season number and put the case back on thr shelf randomly. Find each probability.
P(season 5 in the correct position)
# of ways to succeed: 1*7!
# of possible outcomes: 8!
P(success) = 7!/8! = 1/8
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P(season 1 and 8 in the correct positions)
Ans: 6!/8! = 1/8*7 = 1/56
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P(season 1 through 4 in the correct positions)
Ans: 4!/8!
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P(all even number seasons followed by all odd numbered seasons)
# of ways to pick 4 even: 1
# of ways to pick 4 odd: 1
Ans: 1/8!
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P(all even number seasons in the correct position)
# of ways to get even in order: 1
# of ways to arrange odd: 4!
Ans 4!/8!
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P(season 5 through 8 in any order followed by seasons 1 through 4 in any order)
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Ans: (4!*4!)/8!
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Cheers,
Stan H.
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