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In a country in which people only want boys, every family continues to have children until they have a boy. If they have a girl, they have another child. I
by ez77 16y ago
In a country in which people only want boys, every family
continues to have children until they have a boy. If they
have a girl, they have another child. If they have a boy,
they stop. What is the proportion of boys to girls in the
country?
Thoughts?
- ez77 16y agoSmart-ass, no-way-getting-an-offer answer: if we assume gender selection to be truly random, the answer may be anywhere between 0 and 1, period.
- radq 16y ago> the answer may be anywhere between 0 and 1 0 and infinity, actually. (sorry, couldn't resist)
- jyiin 16y agoIf we assume there's an even chance of having a boy or girl, the proportion of boys to girls is still 50/50. It's basic stats. These are independent events.
- radq 16y agoIts been discussed on MathOverflow: http://mathoverflow.net/questions/17960/google-question-in-a-country-in-which-people-only-want-boys http://mathoverflow.net/questions/17960/google-question-in-a...
- bertm 16y agoA good analogy for this is flipping a coin. What is the proportion of total heads to total tails if a population of people each flip a coin until they get a heads. The answer is fairly trivial, as each coin flip is independent. Given a fair coin, you would expect the answer to be near 1. You could always calculate the variance given the population size using the binomial distribution. A more fruitful question might be: what is the average family size in a country with these birthing habits?