Results 1 to 2 of 2

Thread: Combinatorics?

  1. #1
    Super Member fardeen_gen's Avatar
    Joined
    Jun 2008
    Posts
    539

    Combinatorics?

    There are two children $\displaystyle C_1$ and $\displaystyle C_2$. $\displaystyle C_1$ has 12 different toys and $\displaystyle C_2$ has 13 different toys. Find the number of ways in which $\displaystyle C_1$ and $\displaystyle C_2$ can exchange their toys in such a way that after exchanging they still have same number of toys but not the same set.
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Senior Member pankaj's Avatar
    Joined
    Jul 2008
    From
    New Delhi(India)
    Posts
    318
    $\displaystyle
    \binom{25}{12}-1
    $

    Let us take the toys from both of them.

    Now we select $\displaystyle 12$ toys and give them to $\displaystyle C_{1}$ and the remaining $\displaystyle 13$ to $\displaystyle C_{2}$ which can be done in $\displaystyle \binom{25}{12}$

    This also contain the ways in which they have their original set of toys.

    Hence,the answer is $\displaystyle \binom{25}{12}-1$
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. [SOLVED] Combinatorics.
    Posted in the Discrete Math Forum
    Replies: 16
    Last Post: Jul 20th 2010, 02:29 AM
  2. Combinatorics
    Posted in the Discrete Math Forum
    Replies: 3
    Last Post: Jun 18th 2010, 08:14 PM
  3. Combinatorics
    Posted in the Discrete Math Forum
    Replies: 3
    Last Post: Jun 3rd 2010, 05:24 PM
  4. combinatorics
    Posted in the Discrete Math Forum
    Replies: 1
    Last Post: May 1st 2010, 10:53 PM
  5. Combinatorics
    Posted in the Discrete Math Forum
    Replies: 2
    Last Post: Oct 10th 2009, 06:03 AM

Search Tags


/mathhelpforum @mathhelpforum