Last night seven of my friends went to a local restaurant. They each handed over their coat as they entered. At the end of the evening the staff returned the coats, but they were totally incompetent and randomly handed out the coats to my friends. What is the probability that exactly six of my friends received their own coat?
If you have not tried to solve it, have a go now. For everyone else the answer is after the break.
The answer is…..of course….. zero. If six of my friends have their coats back then all seven must have the right coat. Therefore it impossible for exactly six of them to have the correct coat.
Did you solve it?
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