Simplify the following text for a Grade 11 native English-speaking person.
Original: The winners applied game theory , a field advanced by mathematician John Forbes Nash , to discover the best and most efficient means to reach a desired outcome , taking into account individuals ' knowledge and self-interest , which may be hidden or private .
Simplified: The three Nobel prize winners used game theory work by mathematician John Forbes Nash , to discover the best way to reach a good outcome , without forgetting individual people .