Re:

Combinations in the

In a two-child family, there are four and only four possible combinations o= children. We will label boys B and girls G; in each case the first letter represents the oldest child:

{BB, BG, GB, GG}

When we know that one child is a boy, there cannot be two girls, so the sam=le space shrinks to:

{BB, BG, GB}

Two of the possibilities in this new sample space include girls:

{BG, GB}

and since there are two combinations out of three that include girls, the probability that the second child is a girl is 2/3.

nonsense! possible combinations say nothing about probability<=r>

ps- invention of new kinds of statistical methods from big=data a promising direction... we could talk to steve strogatz or duncan wa=ts about this....