Drunk passenger probability?

An aeroplane with 128 seats has its passengers lined up in order for boarding from seat 1 to 128. Unfortunately, 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... show more An aeroplane with 128 seats has its passengers lined up in order for boarding from seat 1 to 128. Unfortunately, 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 128th passenger will get the 128th seat ?
Update: Thanks, guys, for the response. The correct ans is 1/2, and i'm giving the BA to the 1st correct answerer. Since some are still not convinced, i'm adding a short explanation The drunk (or any passenger who is compelled to take a random seat) can only do so from the vacant seats. Now, as long as #1 and # 128 are... show more Thanks, guys, for the response.
The correct ans is 1/2, and i'm giving the BA to the 1st correct answerer.
Since some are still not convinced, i'm adding a short explanation

The drunk (or any passenger who is compelled to take a random seat) can only do so from the vacant seats. Now, as long as #1 and # 128 are vacant, they have an equal chance of getting occupied. Whichever gets occupied first will determine the final outcome, and since they are equally likely, the probability is 1/2.

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