Results 1 to 4 of 4

Math Help - Probability Question

  1. #1
    Junior Member
    Joined
    Jul 2006
    Posts
    43

    Probability Question

    A company orders supplies from 10 distributors and wishes to place 7 orders. What is the probability that all of the orders go to different distributors?

    The answer is 0.0605, but I'm not sure how you get that. I tried a few things, but I'm not sure. Any help appreciated.
    Follow Math Help Forum on Facebook and Google+

  2. #2
    MHF Contributor

    Joined
    Aug 2006
    Posts
    18,616
    Thanks
    1579
    Awards
    1
    That is Permut(10,7)/10^7.
    There are 10^7 functions from a set of seven to a set of ten.
    If each gets at most one then we have permutations.
    These are injections.
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Junior Member
    Joined
    Jul 2006
    Posts
    43
    Ok. Thanks a lot.

    Along the same lines, what is the probability that distributor I gets exactly two orders and distributor II gets exactly three orders?

    Also, what is the probability that distributors I, II, and III get exactly two, three, and one orders respectively.
    Follow Math Help Forum on Facebook and Google+

  4. #4
    MHF Contributor

    Joined
    Aug 2006
    Posts
    18,616
    Thanks
    1579
    Awards
    1
    Quote Originally Posted by JaysFan31 View Post
    Ok. Thanks a lot.

    Along the same lines, what is the probability that distributor I gets exactly two orders and distributor II gets exactly three orders?
    I probably should have commented in my first reply. We have assumed that the distributors as well as the orders are distinct. The fact that the orders are distinct should have been clearly stated in the question.

    Let C(N,k) be combin(N,k).
    Distributor I can get two in C(7,2) ways and II can then get three in C(5,3) ways. The remaining can be distributed in 8^2 ways.
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Replies: 5
    Last Post: February 10th 2013, 02:11 PM
  2. Probability question involving (A given B type question )
    Posted in the Advanced Statistics Forum
    Replies: 0
    Last Post: November 9th 2009, 09:08 AM
  3. New Probability question
    Posted in the Statistics Forum
    Replies: 2
    Last Post: July 15th 2009, 06:50 AM
  4. probability question
    Posted in the Advanced Statistics Forum
    Replies: 4
    Last Post: May 16th 2009, 06:36 AM
  5. A probability question and an Expectations question
    Posted in the Advanced Statistics Forum
    Replies: 1
    Last Post: January 29th 2006, 06:13 PM

Search Tags


/mathhelpforum @mathhelpforum