Figuring out the maths for the probability of two adopted teens randomly being matched as pen pals in 2003

Say you're a math nerd and someone poses the question randomly. How would you actually go about figuring it out? If one teen is in the US and the other is in Ireland. What does that look like? How accurate could you get? Is there enough data for a reasonable response?

• This question is very vague. It is difficult to provide a mathematically sound answer to this question.

• One would need tons of assumptions to give a numerical answer. After some point, too many assumptions in a model are just self-serving.

• Okay, apologies, this is my first post. How would I make it more specific? In this situation, both of the teens were adopted and surprised to find this out which is why one of them posed what are the odds of them meeting. Imagine it were a conversation you were having with a new acquaintance, would it be possible to work the math out? How would you go about doing it?

• Are you asking for the probability of two wins being pen-pals given that they were separately adopted, or the probability that two orphan twins get adopted and also end up becoming pen pals?

• Separately adopted, one in the US the other in Ireland. They were randomly paired/met as pen pals and had no prior relationship.