Le 4 mai 2021, la plateforme Yahoo Questions/Réponses fermera. Elle est désormais accessible en mode lecture seule. Aucune modification ne sera apportée aux autres sites ou services Yahoo, ni à votre compte Yahoo. Vous trouverez plus d’informations sur l'arrêt de Yahoo Questions/Réponses et sur le téléchargement de vos données sur cette page d'aide.
drunk passenger probability variant?
An aeroplane with 100 seats has passengers lined up in order, for boarding from seat #1 to #100. However, the first passenger is drunk, and will take any of the seats at random. All other passengers will take their own seat if it is vacant, or else take another seat at random.
What is the probability that the 50th passenger will get seat #50 ?
1 réponse
- gianlinoLv 7il y a 9 ansRéponse favorite
Consider seats 1 and 50 up to 100. That's 52 seats
While seating the 49 first passengers exactly one of these seats is taken. Indeed as soon as such is the case all subsequent passengers till 49 will find their seats free.
So one out of these 52 seats is taken when the turn of passenger 50 comes. Hence his seat is taken with probability 1 / 52 and free with probability 51 / 52.
