I have two children, one of whom is a son born on a Tuesday. What is the probability that I have two boys?
If you answered 13/27ths, you'd, evidently, be correct.
It's a bizarre puzzle that stems from the old: Mr. Smith has two children. At least one of them is a boy. What is the probability that both are boys?
One would think the answer is 50/50, since the sex of one child is independent of the sex of the other, but mathematically, that's not the case. Since the boy could either be the younger or the older child, the analysis is a little different. You could have one of the three options:
boy, girl
boy, boy
girl, boy
Which means that only 1/3 options leads to a boy/boy combination.
Take a look at the above article if you're at all interested in math puzzles. It makes for an interesting, if somewhat confusing, read. And makes you wonder what the odds are if someone says, "I have two children. One of them is a hat-wearing, blue-eyed, kazoo-playing, weight-lifting boy who was born in the morning on a Wednesday. What are the odds both my children are boys?"
