## A New Birthday Problem

Last week, Slashdot posted an interesting link to a problem posed at the most recent Gathering 4 Gardner, a mathematical (or perhaps I should say mathemagical) convention created in honor of the late Martin Gardner. The question, posed by Gary Foshee, is as follows: you have a friend with two children, one of whom is a boy born on a Tuesday. What is the probability that the other child is a boy?

Forget about the Tuesday fact for a moment – if you have a friend with two children, one of whom is a boy, what is the probability that the other child is a boy? You might expect that the answer should be 50%, since the sex of one child shouldn’t affect the sex of the other. But this is not quite right, because you’re not told whether the boy is the older or younger child.

There are only . . . → Read More: A New Birthday Problem

## RIP Martin Gardner

Not long ago, I wrote an article in commemoration of Martin Gardner’s 95th birthday. Sadly, it seems this will be my last article in celebration of his birth, as he passed away late last month.

Through his passing, though, his influence has become even more apparent. Perhaps because he published mathematical games in Scientific American for 25 years, the magazine has been the most visible in its veneration of him. There are no less than six articles on Gardner at the SciAm website; while some are reprints of earlier articles, there is also new material from writers and mathematicians who were influenced in some way by Gardner’s unique career. Since I can’t do justice to Gardner the way others already have, let me summarize what you can find if you’re interested in learning more about this stand-up fellow.