A woman has two kids. One is a boy. What are the odds the other is a boy?

God people look at the original problem.

One of the kids is a boy

so these are your only options:

B/B
B/G <-
G/B <-

The two with the arrows ARE separate since its only specified that one of them is a boy and you aren't told which.

So simple math, out of 3 distinct possibilities only 1 works... what are the odds then? cough1/3cough.

And to those of you who say that its 50%:

Its only 50% if you're told that the first kid is a boy or a girl. But since you dont know which of the kids is which, you have those three separate possibilities not just two possibilities.

Ah, but the question is not how many possibilities can be there. It's asking for the gender of a separate child from the other. If the order had any importance, yes, 1/3.

However... We have this two separate possibilities:

OUTCOME #1
Child #1 = Boy
Child #2 = Unknown

Child number 2: 50% chance to be boy - 50% chance to be girl

OUTCOME #2
Child #1 = Unknown
Child #2 = Boy

Child number 1: 50% chance to be boy - 50% chance to be girl

I can't see why it's harder to give birth to another male after giving birth to another. Because, after all, probability is about that.