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bhikkhu

(10,724 posts)

19. Done that way: 100% chance of having a son, 50% chance of having a daughter

Reply to cthulu2016 (Original post)

Sat Jan 12, 2013, 05:22 PM

Jan 2013

So I would imagine (without thinking too hard on it), the odds of any family having one child - a boy - would be 50%. That would be half of families with one male child.

The other half would have a girl, then a 50% chance of having a second child who was a boy - so you'd have 25% of the total with one boy and one girl.

Then that 25% of the total (with two girls each now) would have a 50% chance of a girl or a boy, winding up with 12.5% of the total having a boy and two girls...and so forth.

Without working it all out, I wonder if it would wind up with 2.718 times more girls than boys?

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Fun with Math [View all] cthulu2016 Jan 2013 OP

... Robb Jan 2013 #1

Probability Publiuus Jan 2013 #2

Yes, I should have speciffied a hypothetical 50-50 cthulu2016 Jan 2013 #3

Check out the effect on populations I worked out in #10 with non 50/50 distributions though Recursion Jan 2013 #12

Your post is interesting. See my reply cthulu2016 Jan 2013 #16

There would be more females. Buzz Clik Jan 2013 #4

Try it with a coin cthulu2016 Jan 2013 #6

Yeah, I actually thought about AFTER I posted, and I agree. Buzz Clik Jan 2013 #8

It's the integral of a poisson process Recursion Jan 2013 #5

Your recollection is correct cthulu2016 Jan 2013 #7

Outcomes enumerated are... Speck Tater Jan 2013 #9

Of course, there is another constraint in the problem as posed... DreamGypsy Jan 2013 #21

I also didn't account for twins and triplets... etc. Speck Tater Jan 2013 #23

So, the generalized answer, given the unequal birth rates we observe, plus the effect on population Recursion Jan 2013 #10

Interestingly... Fisher's law is usually expressed wrong cthulu2016 Jan 2013 #14

then for 100 couples hfojvt Jan 2013 #20

China's preference of male babies and one child policy has skewed the ratio... Agnosticsherbet Jan 2013 #11

Without selective abortion, the chances of each birth are still 50:50 muriel_volestrangler Jan 2013 #13

Even without gender-selective abortion ... surrealAmerican Jan 2013 #15

That is an excellent point cthulu2016 Jan 2013 #17

Rosendcrantz and Guildenstern are dead. DreamGypsy Jan 2013 #18

Done that way: 100% chance of having a son, 50% chance of having a daughter bhikkhu Jan 2013 #19

You started out very well, but cthulu2016 Jan 2013 #22

Of course... bhikkhu Jan 2013 #24