All about flooble | fun stuff | Get a free chatterbox | Free JavaScript | Avatars    
perplexus dot info

Home > General
No Incest, Please (Posted on 2005-07-18) Difficulty: 3 of 5
There are three families each with two sons and two daughters. In how many ways can these young people be married so that each couple includes one member of each gender, no couple is brother and sister, and there are no singles left over?

No Solution Yet Submitted by Erik O.    
Rating: 3.6000 (5 votes)

Comments: ( Back to comment list | You must be logged in to post comments.)
re: Off the cuff | Comment 3 of 13 |
(In reply to Off the cuff by Bob Smith)

1) Assume that your scheme works. This scheme does not allow for the real possibility that the first two families will intermarry in both cases, leaving the boys in the third family with no one to marry but their sisters. Since out of the 288 combinations you claimed, there are 8 ways that the third family could get "stuck," there are 288 - 8 = 280 ways left.

2) But then again the scheme does not work to begin with. Giving the first son in the second family 4 choices supposes that both sons in the first family chose his sisters.

 


  Posted by TomM on 2005-07-18 17:11:34
Please log in:
Login:
Password:
Remember me:
Sign up! | Forgot password


Search:
Search body:
Forums (0)
Newest Problems
Random Problem
FAQ | About This Site
Site Statistics
New Comments (9)
Unsolved Problems
Top Rated Problems
This month's top
Most Commented On

Chatterbox:
Copyright © 2002 - 2017 by Animus Pactum Consulting. All rights reserved. Privacy Information