I toss two coins and look at the outcome. I then tell you that at least one of the coins is showing up as "tails". What is the chance that the other one is showing "tails" as well?

(from techInterview.org)

I looked at the official solution, and I've seen that it's apparently 1/3, but I still think its 1/2. If one is tails, the other can still only be heads or tails, so there is a 50-50 chance of it being tails, regardless of what the first one was.

Posted by Lewis on 2003-05-30 06:50:41