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Boys and girls in the village


Best Answer harey, 25 February 2014 - 10:50 PM

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#1 bonanova

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Posted 25 February 2014 - 08:50 PM

In one village boys are desired, to work the land. And so couples are told to be sure they have a boy and then stop having children.

In another village girls are desired, to increase the population. In that village, couples must bear a girl and then stop having children.

The villages are of equal size, and heterosexual monogamy is practiced.

By symmetry, there will a girl in each village for every boy in the other village.

 

But marriages are permitted only within one's own village.

What percentage of children in each village therefore can be expected not to find a mate?


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#2 harey

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Posted 25 February 2014 - 10:50 PM   Best Answer

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#3 bonanova

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Posted 27 February 2014 - 10:36 AM

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I'll mark this solved.

Is there a more succinct solution?


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The greatest challenge to any thinker is stating the problem in a way that will allow a solution.
- Bertrand Russell

#4 harey

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Posted 27 February 2014 - 10:21 PM



Is there a more succinct solution?

 

There is: just the formula giving the number of boys. But it is quite unreadable and to understand it, you have more or less to go thru what I have written.


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