> You're going to say it's 1/3. I most certainly am not. I'm going to say it's 13/27. I agree the imprecise nature of the English language muddies the water s

> You're going to say it's 1/3. I most certainly am not. I'm going to say it's 13/27. I agree the imprecise nature of the English language muddies the water somewhat, but the question can be re-framed to remove this aspect and yet still have people give the wrong answer, and as such is not just a "really rather boring" case of "intentional" "poor communication", but offers an interesting insight into the shortcomings of our intuition for probability. So let's set aside the original problem and put this one instead (which may or may not be equivalent to the original depending on your interpretation, but let's take this in isolation anyway): Woman: How may children do you have? Man: Two. Woman: Is at least one of them a boy who was born on a Tuesday? Man: Yes. What now is the probability the man has two boys? The answer is in fact 13/27, because of the unlikely extra information revealed by the Tuesday condition, which I think is surprising and interesting.