I was gonna send DB a PM with this question, but I figured rather than do that, I'd just bore everyone here instead

DB: In Partagas' thread about the liklihood of 300 game winners in the future, five pitchers are cited (Mulder, Zito, Hudson, Sabathia, and Garcia) as being off to a good start.

I wrote that if there's a group of five, each with a 10% chance, then there is a 50% chance that one of them will do it.

But I know that's incorrect, because if there are ten pitchers with a 10% chance, the chances are certainly not 100%.

I remember a similar question coming up once before, but I don't remember what we decided. Help me out here...