>Instead of:
>
>"Now assume I told you that one of the bears is male. What
>is the probability that both are males? Of the three
>possible outcomes (mf, fm, mm) only the last where both
>bears are male is favorable. The answer is 1/3."
>
>You should say:

>"Now assume one of the bears is male. What is the
>probability that both are males?"

>And now this is correct.

I quite agree with you. However, words are seldom uttered free of any context. So, I assumed that in the context of problem posing the only interesting, surprising, unexpected, etc. formulation is the one you gave. This denied, there is a reason to investigate why I have spoken at all. But then again, one should not assume a common background among all the visitors.

Here what just occurred to me: assuming that one of the bears is male does not change anything. The real bears are either males or females; there is nothing to assume. The correct formulation should be

"Now, it so happened that one of the bears is male. What is the probability that both are males?"