Math problem There are 219 seats in a plane, and there are 219 passengers in a line, coming into the plane in order. Each passenger is assigned a seat. The first person, being careless, forgets his seat number, so he chooses a random seat. From then on, the rest of the passengers come in (one by one). If they find their seat occupied, they randomly choose another. Otherwise, they take they're assigned seat. What is the probability that last passenger finds his/her assigned seat unoccupied