A mother and her friend are talking about how many chidren they have. The friend knows how many daughters the mother has, but doesn't know how many sons she has. The mother says:

"All of my children have the same amount of brothers and the same amount of sisters as the other children."

Now the friend knew how many sons she had. How many sons did the mother have?

 the mother has either 0 children or 1 son or a daughter.

 if she has a daughter or a son, either one of the offsprings will have 0 brothers and 0 sisters, which satisfies the condition thus leading to a correct deduction by the friend in regards to the no of offsprings the mother has.

 the same holds true when the no is zero.

 it's time we move on to something else.

Posted by andy_b on 2005-10-10 12:41:15