Paul Folbrecht wrote:
Obviously, it has to be that a Lyc at 2200 hours is more
likely to fail than one at 200,

Without a careful statistical analysis of engine failures, it's
impossible to say if that's true or not.

Take a brand new engine right out of the factory. It's a reasonable
statement that it's more likely to make it to 200 hours than to 2200.
But, that's not the interesting question.

The interesting question is the one implied above, i.e. whether an
engine which has 200 hours on it is more likely to fail in the next 100
hours of operation as one which has 2200 hours on it. It's called
conditional probability. P(2300) is the probability of making it to
2300 hours. P(2300|2200) is the probability of making it to 2300 hours
GIVEN THAT is has already made it to 2200.