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benmartorano
Newbie

Posts: 48
 airplane riddle   « on: Oct 5th, 2012, 3:03pm » Quote Modify

People are waiting in line to board a 100-seat airplane. Steve is the first person in the line. He gets on the plane but suddenly can't remember what his seat number is, so he picks a seat at random. After that, each person who gets on the plane sits in their assigned seat if it's available, otherwise they will choose an open seat at random to sit in.
The flight is full and you are last in line.

What is the probability that you get to sit in your assigned seat?
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Altamira_64
Junior Member

Posts: 116
 Re: airplane riddle   « Reply #1 on: Oct 10th, 2012, 11:40am » Quote Modify

Let's start by saying that Steve will sit in his own place with probability 1%.
Then the second passenger will sit in his assigned seat with probability 99%.
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towr
wu::riddles Moderator
Uberpuzzler

Some people are average, some are just mean.

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Posts: 13651
 Re: airplane riddle   « Reply #2 on: Oct 10th, 2012, 1:15pm » Quote Modify

I don't think the logic of that is correct; although the conclusion it leads to is.
There is a 1% probability that Steve will sit in the second passengers seat and therefor the second passenger has a 99% chance of sitting in his assigned seat. (i.e. not because Steve has a 1% chance of sitting in his own seat, but because of the 1% chance of him sitting in the second's seat)

Anyway, here's a previous thread for this puzzle.
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Altamira_64
Junior Member

Posts: 116
 Re: airplane riddle   « Reply #3 on: Oct 11th, 2012, 8:20am » Quote Modify

I see.