1. Not finding help here? Sign up for a free 30min tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Probabilit y of a valve falling in a time period

  1. Nov 15, 2007 #1
    1. The problem statement, all variables and given/known data

    A large population of nominally identical "fail to close" control valves are put into service on the same day on similar installations. The number of valve failures per month N was recorded over time and shown to be given approximately by the following equation

    Calculate the probability that the valve fails in the time period (0,24) months

    2. Relevant equations

    N = 0.001 X t^1.26 (failures/month)

    3. The attempt at a solution

    have tried it with the density function and the cumulative distribution function with N being lambda but still far away from the ans of 0.4414

    The second part of the question also has be stumped as it states if the installation contains 3 valves in unrelated parts of the plant, calculate the probability that the installation is free of valve failure over the same time period (ans is 0.1743)
    Last edited: Nov 16, 2007
  2. jcsd
  3. Nov 15, 2007 #2


    User Avatar
    Staff Emeritus
    Science Advisor

    What was the question that 0.4414 is the answer to? I see no question given here!

    What time period?
  4. Nov 16, 2007 #3
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?

Similar Discussions: Probabilit y of a valve falling in a time period