Results 1 to 2 of 2

Math Help - Probability Distributions

  1. #1
    Member
    Joined
    Oct 2008
    Posts
    124

    Probability Distributions

    1) Verify f(x) = (2x)/(k(k+1)) for x = 1,2,3,...,k can serve as the probability distribution function of a random variable with the given range.

    I know this has to satisfy two parts. I got the first part, where for each value in the domain, f(x) >= 0. I am having trouble with the part where the sum has to equal 1. How do I show this?
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Moo
    Moo is offline
    A Cute Angle Moo's Avatar
    Joined
    Mar 2008
    From
    P(I'm here)=1/3, P(I'm there)=t+1/3
    Posts
    5,618
    Thanks
    6
    Hello,
    Quote Originally Posted by noles2188 View Post
    1) Verify f(x) = (2x)/(k(k+1)) for x = 1,2,3,...,k can serve as the probability distribution function of a random variable with the given range.

    I know this has to satisfy two parts. I got the first part, where for each value in the domain, f(x) >= 0. I am having trouble with the part where the sum has to equal 1. How do I show this?
    \sum_{x=1}^k f(x)=\sum_{x=1}^k \frac{2x}{k(k+1)}=\frac{2}{k(k+1)}\sum_{x=1}^k x

    and the sum of the first k integers is \frac{k(k+1)}{2}
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Probability Distributions
    Posted in the Statistics Forum
    Replies: 2
    Last Post: November 16th 2009, 12:01 PM
  2. probability distributions
    Posted in the Statistics Forum
    Replies: 3
    Last Post: October 1st 2009, 03:41 PM
  3. Probability Distributions
    Posted in the Statistics Forum
    Replies: 1
    Last Post: January 6th 2008, 03:30 PM
  4. Probability Distributions HELP
    Posted in the Statistics Forum
    Replies: 2
    Last Post: January 6th 2008, 02:43 PM
  5. PROBABILITY Distributions
    Posted in the Statistics Forum
    Replies: 1
    Last Post: May 16th 2006, 12:34 PM

Search Tags


/mathhelpforum @mathhelpforum