Math geniuses of Veeky Forums

You gotta put a limit on how many kids a couple can physically have....

Let's say this happened in China. There are infinite Chinese. Boom, problem solved.

1:1

Do I get extra points for being a pedantic ass claiming small variables in male/female ratio and similar?

Not really, all you have to do is enable people to stop having children before they get a male.
That way you'll get a bunch of families that only have females

you two try again

The ratio slowly converges to 1, see the graph at wolframalpha.com/input/?i=sum&rawformassumption={"F", "Sum", "sumfunction"} ->"(1/(2^x))*(x-1)"&rawformassumption={"F", "Sum", "sumvariable"} ->"x"&rawformassumption={"F", "Sum", "sumlowerlimit"} ->"1"&rawformassumption={"F", "Sum", "sumupperlimit2"} ->"infinity"&rawformassumption={"C", "sum"} -> {"Calculator"}. The average amount of women per family slowly converges to 1, while the amount of men are always guaranteed to be 1. So the ratio men:women will always be slightly higher than 1 in the real world. That means that there are more men than women because of this new system. The reason for this is that everyone is guaranteed to always have one male child, while the average amount of women will never be higher than 1.

Mistake in my first sentence, that graph doesn't show that the ratio converges to 1, the average amount of women per family converges to 1

The ratio does not change. The only assumption needed for this is that the amount of children a family already has does not influence the gender of any further children.

Sigma (1/2)^n
i = 1

Assuming everyone breeds until they get a boy.

That's assuming that infinitely many girls is possible. No mom can have more than like 15 kids. You gotta make that the upper limit of your "infinite" sum. The ratio must be less than 1.

>tfw outsmarted by a kike

That's what I'm saying, there will always be more men than women assuming nobody has infinite girls.

Oh, k.

He's wrong. Female population would fall.

infinite because all the families kill their female children until they obtain a male because girls are disgusting gross sluts who won't fuck me REEEEEEEEEEEE

Nope. No matter where families stop having children the expected ratio will always be 1. That's because the chance of having a boy is still equal to the chance of having a girl. The number of children or where you stop having children has no effect on that.

The expected number of males per family is the sum from k=0 to inf of P[0]...P[k] / 2^(k+1) where P[n] = the chance of a family having another child after their nth child. The expected number of females turns out to be exactly the same when you do the math.

Well, there's the possibility of one couple having a female child, and then no more. The problem says 'the family can continue to have children'. Can continue is not the same as must continue.

Yeah but that doesn't effect the ratio of male to female. That family was just as likely to have one male child. For every family with only two females there are two families with 1 male etc.

2:1?

Nope.

So you mean the mean quantity of children is affected, rather than the ratio... or am i missing something?

Make as many children as you want and tell said feminists to stop assuming their genders.

The only true answer

Yes.

Ah, you're right! I was still assuming that every family has 1 boy even when there's a cap, while it's actually possible for a family to have 15 girls and no boy.

The expected amount of boys per family would be 1, assuming they all breed until they have a boy. The expected amount of girls is the sum of n/(2^-n) = 2. So the girl:boy ratio is 2:1.

Pretty sure even with 10:1 female ratio the human population would be sustainable. Those few guys just have to do more sex.

If a couple gets a boy, can the guy then go on to impregnate another woman who hasn't had a boy yet?

it should be the sum over n/2^(n+1), which is 1

Uh no it's the sum of n/2^(n+1) assuming families have maximum children.

What's the ratio of male to female among firstborn children? 1:1. Secondborn children? 1:1. Etc.

Should be the same as it is now because no group in their right minds would allow this law to pass.

>feminists
>in their right minds
You're right there user, no group in their right minds would allow this law to pass.

This is a good point, if a woman gets Impregnated right after giving birth you only need a guy to ejaculate In her once every ~280 days.
If a dude can get off twice a day every day then to support a population of 3 billion women to be constantly pregnant would only need 1 guy for every 560 women, just over 5 million men

Inbreeding ahoy

The 80:20 rule would still be in effect. All that happens is that those females will mate with fewer and fewer males as the pool of Chads approaches 0. Extinction occurs.

You literal retards, the way you partition a bunch of random events doesn't change the average.

This is just a Geometric distribution with parameter [math]p = \frac{1}{2}[/math], then you have to look at the expectation -1 or +1, I don't really want to think about it right now.

I was starting to get worried that noone else said this and that I was a brainlet, phew.

is this ambiguous on purpose?

Did you just assumed the gender of theses childrens ?

You don't have to look at the expectation of anything. Every time you have a child, the probability of having a boy is 1/2. It doesn't matter what stopping conditions your impose, this will remain unchanged.

Still equal numbers obviously

>infinite Chinese people
This is a really big problem in and of itself.

50% will have a boy, 50% will have a girl, and then possibly another child after that. That child will also have equal chances of being a boy or girl. So it really doesn't matter that there will only be second, third etc. children if the previous child was female. Every ordinal instance will have a 50/50 distribution, and this will therefore be the total distribution as well.

Literally what they're doing is they're making the average number of kids in a family close to 2 kids.