SOLUTION: The man picks 1 from each of the following short stories every night and reads one short story from each of the following catagories: 1 of 5 mysteries, 1 of 4 non-fiction, 1 of 6 t

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Question 437758: The man picks 1 from each of the following short stories every night and reads one short story from each of the following catagories: 1 of 5 mysteries, 1 of 4 non-fiction, 1 of 6 teen tales, 1 of 3 Robin Cook books, and and 1 of 5 historical novels. How many options does he have if he must start and end with either a mystery or a teen tale?Can you help with an explanation of how to go about solving a simpler problem too? I am so stuck. I think it is a permutation???
Answer by josmiceli(19441) (Show Source):
You can put this solution on YOUR website!
I think it may be simpler than it looks.
The man could choose from the categories in
any order he wishes except for the 1st and last night.
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The problem is hard to interpret. I think they are talking about
5 successive nights that he reads a single short story.
I don't think I can go beyond 5 successive nights because
I don't know how many short stories are in each book.
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I'll use 1 letter for each category:
M - 5
N - 4
T - 6
R - 3
H - 5
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total - 23
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The 1st night, he chooses between
M - 5
T - 6
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total - 11 ways to choose
2nd night: there are 23 - 1 = 22 possible ways he can choose
3rd night: there are 23 - 2 = 21 possible ways he can choose
4th night: there are 23 - 3 = 20 possible ways he can choose
5th night: there are 11 - 1 = 10 possible ways he can choose
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The choices must be multiplied to get all the possible orders

There are 1,016,400 possible orderings of short stories he can
read on 5 successive nights
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You should get a 2nd opinion on this, too. These kind of
problems can be very tricky, but they are good for the brain.