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please help me with this question, it would be highly appreciated:
3 tiles with the letter X on them and 3 tiles with the letter O on them are placed in a row.
The order is chosen at random. What is the probability that no two adjacent tiles have the same letter on them?
Thank you taking time out of your day to help me!
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One such base configuration is XOXOXO,
with 3! = 6 permutations of X's and 3! = 6 permutations of O's; in all 6*6 = 36 possible permutations inside this configuration.
Similarly, there are 36 possible permutations inside the other base configuration OXOXOX.
In all, there are 36 + 36 = 2*36 = 72 favorable permutations among 6! = 6*5^4*3*2*1 = 720 all possible permutations of 6 letters.
In terms of probability, it is P = 72/720 = 0.1 to have a preferable configuration, randomly.
Solved and explained.