Statistics for Maintenance Modelling: Continuous Lifetime Distributions 1

# Combining the Probability Density Function and the Reliability Function¤

So, if an item has lasted (survived) 2 years, how do you work out the probability that it fails in its third year?

This is not as this ignores the fact that many items do not make it to the end of year 2. In fact only R(2) of the items make it past year 2 and so the number who fail in year 3 as a fraction of those that make it past year two is:

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