100 passengers are boarding a plane with 100 seats. The first passenger in line has lost his boarding pass and chooses a random seat to sit in. Each subsequent passenger takes their assigned seat if it is unoccupied. Otherwise, they take a random unoccupied seat.
What is the probability that the last passenger will find their seat unoccupied?
50%
There are only two possibilities. The seat is their assigned seat or its the first passengers seat.
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