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

Find a formula for p(x) = P(X=x)

  1. Oct 20, 2009 #1
    Find a formula for p(x) = P(X=x) ....

    So I have a test tomorrow and this question is in a list of review questions and I'm having trouble remembering where the mu fits into the formula. Any help would be greatly appreciated :)

    Question: Suppose that X is a random variable with just two possible values a and b. For x = a and b find a formula for p(x) = P(X = x) in terms of a, b and mu = E(X).
  2. jcsd
  3. Oct 20, 2009 #2


    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    Re: Find a formula for p(x) = P(X=x) ....

    If P(X=a)=p and P(X=b)=1-p, what can you say about E(X)?
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook