Search All of the Math Forum:

Views expressed in these public forums are not endorsed by NCTM or The Math Forum.

Notice: We are no longer accepting new posts, but the forums will continue to be readable.

Topic: Permutation problems
Replies: 13   Last Post: Aug 12, 2013 2:23 PM

 Messages: [ Previous | Next ]
 Ben Brink Posts: 201 From: Rosenberg, TX Registered: 11/11/06
RE: Permutation problems
Posted: May 19, 2012 8:30 PM
 att1.html (1.1 K)

Mahesh,
Now I see how you get A, B and C. The latest post seems to point toward a solution.
Thanks,
Ben

> Date: Sat, 19 May 2012 02:35:41 -0400
> From: discussions@mathforum.org
> To: discretemath@mathforum.org
> Subject: Re: RE: Permutation problems
>
> I could make some progress after your reply. I thought of doing it other way round. So now the sets are:
> A: Contain fish |A|=23!
> B: Contain rat |B|=24!
> C: Contain bird |C|=23!
> A n B: 21!
> A n C: 20!
> B n C: 21!
> A n B n C: 18!
>
> A' n B' n C'= Total permutations - (A u B u C)
> = 26!-(23! + 24! + 23! - 21! - 20! - 21! +18!)
> =4.0261.... * 10 ^ 26
> Let me know if this is correct.
> Thank you.

Date Subject Author
5/18/12 Mahesh
5/18/12 Ben Brink
5/19/12 Mahesh
5/19/12 Ben Brink
5/19/12 Angela Richardson
5/19/12 Ben Brink
5/20/12 Peter Scales
5/22/12 Ben Brink
8/11/13 Mark Rickert
8/11/13 Ben Brink
8/12/13 Mark Rickert
8/12/13 Ben Brink
8/12/13 Peter Scales
8/12/13 Ben Brink