The time between failures for a software system is: failure 1 – 6 hours, failure 2 – 4 hours, failure 3 – 8 hours, failure 4 – 5 hours, failure 5 – 6 hours. The reliability of the system for one hour of operation, assuming an exponential model, is

1. Ae^(−9/29)
2. Be^(−7/29)
3. Ce^(−5/29)
4. De^(−3/29)

Pick an option to check yourself, or open the answer below.

Show answer & explanation

Correct answer: C. e^(−5/29)

Explanation

MTTF = (6 + 4 + 8 + 5 + 6)/5 = 29/5 hours, so λ = 5/29 per hour. R(1) = e^(−λ·1) = e^(−5/29).