A woman has two kids, one of them is a girl

Salami · 03-02-2013, 03:47 PM

The probability is completely independent of whether or not the first child is a boy. When you toss a coin 99 times and get 99 heads, the probability of the next toss being a head is still 50%. However the chances of getting 100 heads in a row in the first place are very low.

Don't think there are any other biological factors to worry about here, the fertilised egg has even chances of gotting a Y chomosome as it has of not getting it.

**Exo** · 03-02-2013, 03:47 PM

Quote:

Originally Posted by Janszoon

Haha! But, really, the whole world is girls.

I'm a lady?

Bane of your existence · 03-02-2013, 03:49 PM

I'm going to say that at first, it's 50% that it's a girl. But you've already said one is a girl. Now, intuitively I want to say that it's obviously not 100% that the other kid is a boy, obviously. But I don't think you halve the remaining 50% for the next child either, so I went with 33%.
I wish I could justify my answer better. But all I have is that it seems like it's in between 50 and 25 for me.

midnight rain · 03-02-2013, 03:51 PM

Quote:

Originally Posted by Burning Down

Not that I think it would matter a whole lot, but do the kids have the same father? I read once during an anthropology class that if a couple has one child, subsequent children are more likely to be of the same gender as the first child. This theory wouldn't apply if the children had different fathers, because it's something to do with the process of meiosis in the man's body, and every man is different.

Same father: I'll say 66% more likely that the other child is also a girl. Not a poll option but I could add it for you if you want. (You already have 33% up there.)

Different father: 50% or less.

Yep same father

**Janszoon** · 03-02-2013, 03:57 PM

Quote:

Originally Posted by Exoskeletal

I'm a lady?

Yep.

Burning Down · 03-02-2013, 04:15 PM

Quote:

Originally Posted by Tuna

Yep same father

Okay yeah, my vote stands at 66% likely that the second child is also female. It's a trend that I've also noticed with people that I know - a lot of them who have siblings tend to have more siblings of one gender then the other.

**Exo** · 03-02-2013, 04:22 PM

Quote:

Originally Posted by Janszoon

Yep.

Finally. Now I can be fabulous.

**Scarlett O'Hara** · 03-02-2013, 04:26 PM

I chose 100% for fun. It's all about probability but in this case also biology.

**Goofle** · 03-02-2013, 04:32 PM

Gotta be 50%. I asked Yahoo.

midnight rain · 03-02-2013, 04:48 PM

Ok two things:

1.) As Vanilla said, the emphasis is on probability and biology, but moreso probability.

2.) It's a counterintuitive problem.

View Poll Results: What are the chances the other is also a girl?
0%	1	9.09%
25%	0	0%
33%	4	36.36%
50%	5	45.45%
100%	1	9.09%
Voters: 11. You may not vote on this poll

03-02-2013, 04:26 PM	#18 (permalink)
Scarlett O'Hara Make it so Join Date: Oct 2005 Posts: 6,181	I chose 100% for fun. It's all about probability but in this case also biology. __________________ "Elph is truly an enfant terrible of the forum, bless and curse him" - Marie, Queen of Thots

03-02-2013, 03:47 PM	#11 (permalink)
Salami Get in ma belly Join Date: Oct 2011 Location: Derbyshire Posts: 1,385	The probability is completely independent of whether or not the first child is a boy. When you toss a coin 99 times and get 99 heads, the probability of the next toss being a head is still 50%. However the chances of getting 100 heads in a row in the first place are very low. Don't think there are any other biological factors to worry about here, the fertilised egg has even chances of gotting a Y chomosome as it has of not getting it.

03-02-2013, 03:49 PM	#13 (permalink)
Bane of your existence Such That Join Date: May 2007 Location: Austin, Tx Posts: 1,197	I'm going to say that at first, it's 50% that it's a girl. But you've already said one is a girl. Now, intuitively I want to say that it's obviously not 100% that the other kid is a boy, obviously. But I don't think you halve the remaining 50% for the next child either, so I went with 33%. I wish I could justify my answer better. But all I have is that it seems like it's in between 50 and 25 for me.

03-02-2013, 04:48 PM	#20 (permalink)
midnight rain Music Addict Join Date: Mar 2009 Posts: 1,711	Ok two things: 1.) As Vanilla said, the emphasis is on probability and biology, but moreso probability. 2.) It's a counterintuitive problem.