Hi everyone, a friend once emailed me a crazy multiple choice question. I thought about it for a while but then gave up. I can't find it anymore, but I remember it was something like: What is the probability of answering this question correctly? 1) 100% 2) 50% 3) 33% Does anybody know what the actual question may have been (as I guess it's pretty well known in mathematical circles) and especially, what the answer is? Thanks!