3 people are blind-folded and a hat (chosen from 3 white and 2 red) is placed on their heads. Person 1 removes his blind-fold and looks at the colors of the hats on persons 2 and 3 then is asked to guess the color on his head. Person 1 is unsure, this is a correct response. Persons 2 and 3 hears this response from person 1. Now, Person 2 does the same, he is unsure, which is correct as well. Person 3 hears the responses from persons 1 and 2. Person 3 does not remove his blind-fold, but is absolutely sure that there is a white hat on his head, this is correct. Can you prove it?