I think there is a mistake in the game of chance brain-warping probabilities.

It is about the boy-girl paradox. The problem goes like this. If there is two girls and you know at least one of them is a girl what is chance that the both of them are girls. And im arguing that the answer should be 1/3 not 1/2 since there are three possible outcomes GB BG and GG

#Combinatorics

Easy Math Editor

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Comments

Going to guess you mean here: https://brilliant.org/practice/the-boy-or-girl-paradox/?p=6

A) “I have two children. No hint this time. Are they both girls?”

Choices are GG, GB, BG, BB; probability of GG is 1/4.

B) “I have two children. At least one of the children is a girl, are they both girls?”

Choices are GG, GB, BG: probability of GG is 1/3.

C) “I have two children. The older child is a girl, are they both girls?”

Perhaps this is where you're having the issue? Out of GG, GB, BG, BB, using the order as older-younger the only two that apply here are GG and GB. That means the probability of GG is 1/2.

Jason Dyer Staff - 3 years, 7 months ago

Oh now i get it :)

tero uusimaa - 3 years, 7 months ago

By the way, in the future, if you click on the three dots (marked "More") with a problem, you can "report" a problem and then it's much easier for us to tell what problem you mean and faster to resolve the report.

Jason Dyer Staff - 3 years, 7 months ago

Thank. You

tero uusimaa - 3 years, 7 months ago

Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$