Answer :
You ask either guy: Which door would the other guy say the money is behind. Then pick the other door. This is why: if you ask the truth teller, who will tell you the door the liar will tell you, the wrong door. If you ask the liar, he will tell you the wrong door, because he lies about what door the truth teller would say. In either case, they give you the wrong door, so you choose the other.
It doesn't matter which man you ask. The answer you get will tell you
where the million $ is, although you still won't know whether the man
you asked was the liar or the truther. (But who cares about that. Right ?)
Pick either 'guard',and ask him:
" IF I were to ask you 'Is the money behind your door ?', would you say 'Yes' ? "
where the million $ is, although you still won't know whether the man
you asked was the liar or the truther. (But who cares about that. Right ?)
Pick either 'guard',and ask him:
" IF I were to ask you 'Is the money behind your door ?', would you say 'Yes' ? "