LOL @ this brain teaser I got on a quantitative finance website:

[Lucky Luciano]

It is actually a good question, but you will have no chance unless you are mathematically inclined. Either way, it is a funny question:

100 people are in line to board Airforce One. There are exactly 100 seats on the plane.

Each passenger has a ticket. Each ticket assigns the passenger to a specific seat. The line of passengers boards Airforce 1, one at a time.

GW is the first to board the plane. He cannot read, and does not know which seat is his.

In order to cover up his inability, he picks a seat at random and pretends that it is his proper seat.

The remaining passengers board the plane one at a time. They all know that GW cannot read, but none of them has the guts to point it out, so they play along with GW.

If one of them finds their seat empty, they will sit. If they find that their seat is already taken, they will pick a seat at random.

This continues until everyone has boarded the plane and taken a seat.

What is the probability that the last person to board the plane sits in their proper seat?

What is the expected number of people sitting in their proper seats?
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The solution is at:

http://www.wilmott.com/messageview.cfm?catid=26&threadid=23067