- #1
chrisyuen
- 56
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Homework Statement
7 distinct flags are hoisted in a post. Find the number of ways of arranging them if
2 of the flags must be separated. (The answer is 3600)
Homework Equations
Permutation: n!
Circular Permutation: (n-1)!
The Attempt at a Solution
1: Flag 1, 2: Flag 2:
The arrangements should be:
1 X 2 X X X X
X 1 X 2 X X X ...
2 X 1 X X X X
X 2 X 1 X X X ...
1 X X 2 X X X
X 1 X X 2 X X ...
2 X X 1 X X X
X 2 X X 1 X X ...
...
I don't know how to calculate the solution provided.
Can anyone tell me how to solve the above problem?
Thank you very much!