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?

The solution is possible only when the two boys of one family marries one girl from each of the other family & two girls of one family marries one boy from each of the other family. The remaining two pairs are automatically fixed.

Hence possibilities of this are 2X2X2X2 = 16 

BBGG

Posted by salil on 2006-02-20 08:16:10