Eddy... you keep on bringing up Rob's comments that favored the answer of 1/11. He explained that, as I have. Yes, 1/11 is an appropriate answer until you look at the specifics of the question we are considering. Rob has recognized the fine point of the question which is something you still can't do. Regnis has also recognized this fine point. Redietz has also recognized this fine point. This is why the answer is 1/6.