Provability for bomb in a flight in 2004, 2005, 2006: 6 * 10^-6
Provability for bomb in a flight in 2007: 5 * 10^-6
Question: A person flew twice in 2005, once in 2006 and once in 2007. How big is the provability for a bomb in a plane in all those 4 flights? How big is the provability for at least one safe flight?
