Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

I Exponential Distribution Question

  1. Apr 26, 2017 #1
    Hi all,
    Can anyone teach me this problem ? Thanks

    The life of a tiger is exponentially distributed with a mean of 15 years.If a tiger is 10 years old, what is the expected remaining life of the tiger?

    A 5 years
    B 10 years
    C 15 years
    D Longer than 15 years
     
  2. jcsd
  3. Apr 26, 2017 #2

    StoneTemplePython

    User Avatar
    Gold Member

    Can you tell me your understanding of 'memorylessness'? What distributions have this property and what does it mean?
     
  4. Apr 26, 2017 #3
    It means the probability distribution of the remaining time until the event occurs always is the same, regardless of how much time (s) already has passed. So I'm guessing the answer is 5?
     
  5. Apr 26, 2017 #4

    StoneTemplePython

    User Avatar
    Gold Member

    so if the probability distribution is the same whether 0 years have passed or 7 years have passed, then what does that tell you about forward looking expectations?

    Also do you know which distributions exhibit memorylessness? (There are only 2....)
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted