Probability a device will fail in its last year of warranty

Question

I have a device with a 5 year warranty.

I want to know what the chance is that it will fail in its last year of warranty cover.

The device fails on average 1 time in every 10 years

Answer 1

Use Poisson Distribution Formula to find probability:

P(x; μ) = (e^-μ) (μ^x) / x! where μ is average failure time of 10 years, x is the last year of the warranty (5 years) and e is approximately equal to 2.71828.