Quick Logic Problem

Actually, we can eliminate the first child's gender from consideration as that has been established.

So the possibilities remain (including both mothers):

Boy - boy
Boy - girl (or Girl - boy; the order doesn't matter)
Girl - girl

Darnit, the answer really is 33%!

Actually it does matter. It is the same as the dice scenario. For 11 you have a 5-6 combo and a 6-5 combo.

Dano just told me their are more than four possibilities.
 
No, there are not. Unless you are going to suddenly tell us that one of the children in question is the step child of Jane and birth child of Joan.

The boy portion on one child for each is fixed. Each has one. So each of the other probabilities is listed.

Yes there are more.
Hint: Think of the kin in chronological order.
 
Actually, we can eliminate the first child's gender from consideration as that has been established.

So the possibilities remain (including both mothers):

Boy - boy
Boy - girl (or Girl - boy; the order doesn't matter)
Girl - girl

Darnit, the answer really is 33%!

Sure about that are you? ;)
 
Sure about that are you? ;)

No, I'm confusing myself. I revert back to my original answer. We already know the gender of the first child. Unless I've read the original question incorrectly and more children are involved, which wouldn't affect the answer unless you're limiting it to only 2 boys and not "at least" 2 boys each. If twins are involved ... Never mind, I'm going to reread the original question.
 
No, I'm confusing myself. I revert back to my original answer. We already know the gender of the first child. Unless I've read the original question incorrectly and more children are involved, which wouldn't affect the answer unless you're limiting it to only 2 boys and not "at least" 2 boys each. If twins are involved ... Never mind, I'm going to reread the original question.

See I did that a bunch of times and the only play on the wording is that he specifies the relative age of one of the children. The question is worded in a way that leaves little room for deception.

So I'm really curious to see the answer to this, since it apparently defies mathematics and genetics.
 
Easy man, this is just a bit of fun.
To answer your question, you need to reread the original problem very closely.

Another (bigger) hint: It is certainly true that Joan has a 1 in 2 shot of having 2 boys.

Does it have something to do with the tense "oldest" child vs. "older" child; the problem states that each has two children, not that each has at least two children.

At least one of Joan's children is a boy. In standard logic problems that language tells us not to make any assumptions about the second child. On the other hand, "oldest" implies at least three, but only two were acknowledged.
 
What he is trying to say is that you have more options....

Because Joans kids are fixed... the oldest is a boy. Janes are not fixed. She could have girl boy or boy girl.

Thus the possibilities
boy girl boy boy
boy girl boy girl
boy boy boy boy
boy boy boy girl
girl boy boy boy
girl boy boy girl

16.6666666666666666666666666666666666666666666666666666%

But wait, that does not exist, because of rounding. You can't have a number like that. Whatever shall we do.
 
Does it have something to do with the tense "oldest" child vs. "older" child; the problem states that each has two children, not that each has at least two children.

At least one of Joan's children is a boy. In standard logic problems that language tells us not to make any assumptions about the second child. On the other hand, "oldest" implies at least three, but only two were acknowledged.

They each have 2 children. Joan's children are not related to Jane's children.
 
What he is trying to say is that you have more options....

Because Joans kids are fixed... the oldest is a boy. Janes are not fixed. She could have girl boy or boy girl.

Thus the possibilities
boy girl boy boy
boy girl boy girl
boy boy boy boy
boy boy boy girl
girl boy boy boy
girl boy boy girl

16.6666666666666666666666666666666666666666666666666666%

But wait, that does not exist, because of rounding. You can't have a number like that. Whatever shall we do.

DING DING. The winner!
 
What he is trying to say is that you have more options....

Because Joans kids are fixed... the oldest is a boy. Janes are not fixed. She could have girl boy or boy girl.

Thus the possibilities
boy girl boy boy
boy girl boy girl
boy boy boy boy
boy boy boy girl
girl boy boy boy
girl boy boy girl

16.6666666666666666666666666666666666666666666666666666%

But wait, that does not exist, because of rounding. You can't have a number like that. Whatever shall we do.

The birth order doesn't matter. The other child is either a girl or a boy in each of the two families.
 
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