Reliability

When the failure rate λ is constant, which expression gives the probability of no failure up to time t (reliability) R(t)?

  1. Aλt
  2. B1 / (λt)
  3. Cexp(−λt)
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Answer: C. exp(−λt)

In the random failure period with a constant failure rate, time to failure follows an exponential distribution and reliability is R(t) = exp(−λt). The mean time to failure (MTTF) is then 1/λ.

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