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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

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Posted 20 February 2013 - 06:30 AM

In a society in which people only want girls every family continues to have children until they have a girl. If they have a boy, they have another child. If they have a girl, they stop. What is the proportion of girls to boys in this society?
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### #2 bonanova

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Posted 20 February 2013 - 09:14 AM

Spoiler for Looks like

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

### #3 witzar

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Posted 20 February 2013 - 11:40 AM

Spoiler for reversal

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Posted 20 February 2013 - 01:40 PM

Spoiler for reversal

there is a 50% chance of having a boy or girl in this society since it wasn't implied. I should had stated it as being stacked in the favor of boys to make the ratio more fun, but oh well

Edited by BMAD, 20 February 2013 - 01:41 PM.

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### #5 Yoruichi-san

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Posted 20 February 2013 - 07:02 PM

Spoiler for Series are not my strong point...

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Women are definitely stronger. We are [Fe]males, after all...

Some of what makes me me is real, some of what makes me me is imaginary...I guess I'm just complex. ;P

<3 BBC's Sherlock, the series and the man. "Smart is the new sexy."

Chromatic Witch links now on my 'About Me' page! Episode 3 is finally here!

When life hands me lemons, I make invisible ink.

### #6 Prime

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Posted 20 February 2013 - 07:08 PM

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

Spoiler for my calculation

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Past prime, actually.

### #7 Prime

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Posted 20 February 2013 - 07:35 PM

Oops, seems I messed up again.

Spoiler for More girls

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Past prime, actually.

### #8 bonanova

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Posted 20 February 2013 - 07:41 PM

Spoiler for Consider

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

### #9 bushindo

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Posted 20 February 2013 - 09:17 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

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### #10 Prime

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Posted 20 February 2013 - 09:18 PM

Spoiler for Marriage procedure

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Past prime, actually.

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