Ahh i see. It's because the ordering doesn't matter. If the question made the ordering matter; "I have two children, the youngest is a boy, what is the probabi

Ahh i see. It's because the ordering doesn't matter. If the question made the ordering matter; "I have two children, the youngest is a boy, what is the probability that i have two boys" Then it's definitely 50%. The truth table would be Youngest: Boy Oldest: Girl Youngest: Boy Oldest: Boy Youngest: Girl Oldest: Girl Youngest: Girl Oldest: Boy With the bottom two being ruled out by the question. I think that's the part that catches people out here.