Ned, Red, Ted and Zed are identical quadruplets alike in every way except one: the way that they describe the children in families that have two children.

1. Ned says one is a boy, if that is a true statement; otherwise he says one is a girl.

2. Red says one is a girl, if that is a true statement; otherwise he says one is a boy.

3. If the older child is a boy, Ted says one is a boy; otherwise he says one is a girl.

4. Zed flips a coin and considers the taller (heads) or shorter (tails) child.

If the coin-selected child is a boy, he says one is a boy; otherwise he mentions the sex of the other child.

One of the four men, we don't know which, then tells us:

"Ok, so Teanchi and Beanchi are a married couple (dont ask me whose he and whose she)!

They have two kids, one of them is a girl."

What is the probability that the other child is a girl?

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## bonanova

Ned, Red, Ted and Zed are identical quadruplets alike in every way except one: the way that they describe the children in families that have two children.

1. Ned says one is a boy, if that is a true statement; otherwise he says one is a girl.

2. Red says one is a girl, if that is a true statement; otherwise he says one is a boy.

3. If the older child is a boy, Ted says one is a boy; otherwise he says one is a girl.

4. Zed flips a coin and considers the taller (heads) or shorter (tails) child.

If the coin-selected child is a boy, he says one is a boy; otherwise he mentions the sex of the other child.

One of the four men, we don't know which, then tells us:

"Ok, so Teanchi and Beanchi are a married couple (dont ask me whose he and whose she)!

They have two kids, one of them is a girl."

What is the probability that the other child is a girl?

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