Bomb Probabilities

A man who travels a lot was concerned about the probability of a bomb on his plane. He found the probability of a bomb was low, but found a way to improve his odds. He now always travels with a bomb in his suitcase. He reasons that the odds of two bombs on the same plane are infinitesimal.

Gang --

I stole this joke from John Allen Paulos, and if you like this joke, you might want to check him out. He has written several books with the same general approach -- there is much humor in mathematics. From the mainstream threads, it is clear to me that many of you use mathematics and spreadsheets on a daily basis, both in pursuit of our hobby and to earn the bucks that feed our hobby. This one came from JAP's book "Innumeracy" (the mathematical counterpart of of illiteracy).

John would be disappointed that this thread has only a 2.0 rating. A fun use of math would be to rate it myself as a 10.0, and see what happens to the rating. If the rating jumps to 6.0, I will know that only one curmudgeon rated it, and rated it as a 2.0. Other results of adding my rating would be a math challenge worthy of study. For example, if I posted a 10.0, and the rating jumped to 4.7, what conclusions can I draw? Can I figure out how many people rated it? Can I guess their individual ratings?