There is an unfair coin. It tends to land on one side more than on the other. It is unknown which side is it.
There is Mr. A and Mr. B. They argue about something and they want to use that coin to decide who is right.
Is there any technique of using that unfair coin to get fair result?
My solution: I can think of only that there is going to be 2 rounds. First time Mr. A chooses HEAD, than Mr. B chooses HEAD if any of them wins twice they win.