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# A society that prizes girls

Best Answer bonanova, 21 February 2013 - 04:23 AM

Spoiler for Think bonanova and prime are correct

Since it's solved, I won't spoiler this.

The answer is not complex. Every birth, regardless of anything that is said, done, legislated, prohibited, presupposed, calculated, imagined or hoped for, has equal chances of being a boy or girl.

If you flip a coin an odd number of times, then, yes, the number of heads and tails cannot be equal. But the question is for large numbers of conceptions and births - for a society - where, even though the numbers of boys and girls may not be exactly equal at every moment - each birth changes the running total - the chances of an excess of boys exactly equals the chances of an excess of girls. The question asks whether a birth control strategy can affect the society's overall gender balance in a systematic way. The answer is no, it can not.

No calculus needed.

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13 replies to this topic

### #11 bonanova

bonanova

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Posted 20 February 2013 - 09:39 PM

Spoiler for Series are not my strong point...

>The number of people in the society is not specified either. I assume, there are n married couples.

Spoiler for my calculation

I think there is a discrepancy with bonanova's answer because...

Spoiler for

Sure. The gender distribution within families is terribly skewed.

1. A family can have an unlimited number of boys; a family can never have more than one girl.
2. A family can have a girl with no brothers [half!]; a family can  never have a boy with no sisters.

• 0
The greatest challenge to any thinker is stating the problem in a way that will allow a solution.
- Bertrand Russell

### #12 Prime

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Posted 21 February 2013 - 12:19 AM

The series is infinite, and the variable term thus equals zero. There are equal numbers of boys and girls on average. Bonanova is right. It's a happy ending. In each generation everyone gets his/her mate.

• 0

Past prime, actually.

### #13 phaze

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Posted 21 February 2013 - 01:14 AM

Spoiler for Think bonanova and prime are correct

Edited by phaze, 21 February 2013 - 01:14 AM.

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Perfecting Mafia suicide since August 2008

### #14 bonanova

bonanova

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Posted 21 February 2013 - 04:23 AM   Best Answer

Spoiler for Think bonanova and prime are correct

Since it's solved, I won't spoiler this.

The answer is not complex. Every birth, regardless of anything that is said, done, legislated, prohibited, presupposed, calculated, imagined or hoped for, has equal chances of being a boy or girl.

If you flip a coin an odd number of times, then, yes, the number of heads and tails cannot be equal. But the question is for large numbers of conceptions and births - for a society - where, even though the numbers of boys and girls may not be exactly equal at every moment - each birth changes the running total - the chances of an excess of boys exactly equals the chances of an excess of girls. The question asks whether a birth control strategy can affect the society's overall gender balance in a systematic way. The answer is no, it can not.

No calculus needed.

• 0
The greatest challenge to any thinker is stating the problem in a way that will allow a solution.
- Bertrand Russell

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