Passengers
In a queue, 100 passengers are waiting for the shipment in a airplane.
Each of them has a ticket for each of the 100 seats in the airplane. (For convenience, let's say the passenger n in the queue has a ticket for the seat number n )
Unfortunately, the first person in line is mad, and will ignore the seat number on their ticket, picking a random seat to occupy. All other passengers are quite normal, and go to their proper places, unless it is already occupied. If it is occupied, they will find a free place to sit, randomly.
What is the probability (in %) that the person 100, being the last to board the airplane will sit in seat 100?
The answer is 50.
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1 solution
If the mad guy goes to his seat, the normal guy will pick the first one, and if the mad guy picks any other seat, it won't bother the 100 number normal guy. So, 50%