Results 1 to 2 of 2

Math Help - Counting question

  1. #1
    Junior Member
    Joined
    Dec 2008
    Posts
    68

    Counting question

    4 books of mathematics ,6 books of physics and 2 books of chemistry are to be put on a shelf . How many arrangments are there if the books of the same subject have to be grouped together ???
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Ant
    Ant is offline
    Member
    Joined
    Apr 2008
    Posts
    137
    Thanks
    4

    Re: Counting question

    3! (4! X 6! X 2!)

    There are n! ways of arranging n objects. So we get, for example, 6! ways of organising the physics books. But we multiply but 3! because there are 3 catagories of books and so 3! ways of ordering these catagories.
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Counting Question
    Posted in the Discrete Math Forum
    Replies: 3
    Last Post: March 7th 2010, 12:20 PM
  2. counting question
    Posted in the Discrete Math Forum
    Replies: 2
    Last Post: February 7th 2010, 02:45 PM
  3. counting question
    Posted in the Discrete Math Forum
    Replies: 2
    Last Post: October 8th 2009, 04:30 PM
  4. Another Set Counting Question
    Posted in the Pre-Calculus Forum
    Replies: 10
    Last Post: January 4th 2009, 07:42 PM
  5. Counting question?
    Posted in the Discrete Math Forum
    Replies: 6
    Last Post: May 18th 2008, 05:47 PM

Search Tags


/mathhelpforum @mathhelpforum