There are four balls in a hat: a blue one, a white one, and two red ones. Now I draw simultaneously two balls, look at them, and announce that at least one of them is red.

What is the chance that the other is red as well?

(In reply to re: I agree with Brian by Charlie)

I think the difference in the two current answers is in the interpretation of what is really being said when the person states "at least one of them is red".  Now to me, this should be taken at face value and should only mean that at least one of the balls is red, but we don't know which one.  So in the case of two red balls being drawn the statement is still valid as it does not make any claim about which of the two balls are red, and thus we do not need to take into consideration of choice of subject.

Posted by Daniel on 2017-05-19 23:38:41