SOLUTION: An algebra class has 8 students and 8 desks. For the sake of variety, students change the seating arrangement each day. How many days must pass before the class must repeat a seati

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Question 1023309: An algebra class has 8 students and 8 desks. For the sake of variety, students change the seating arrangement each day. How many days must pass before the class must repeat a seating arrangement?
Suppose the desks are arranged in rows of 4. How many seating arrangements are there that put Larry, Moe, Curly, and Shemp in the front seats?
What is the probability that Larry, Moe, Curly and Shemp are sitting in the front seats?

Answer by Edwin McCravy(20086) About Me  (Show Source):
You can put this solution on YOUR website!
An algebra class has 8 students and 8 desks. For the sake
of variety, students change the seating arrangement each day.
How many days must pass before the class must repeat a
seating arrangement? 
8! = 40320

Suppose the desks are arranged in rows of 4. How many seating
arrangements are there that put Larry, Moe, Curly, and Shemp
in the front seats? 
4! ways they can go in the front seats. For each of those 
ways, there are 4 ways that the other 4 can be placed in the 
back row. That's 4!*4! = 24*24 = 576

What is the probability that Larry, Moe, Curly and Shemp are
sitting in the front seats? 
576 ways out of 40320 or 576%2F40320%22%22=%22%221%2F70

Edwin