Imagine a number of baseball pitchers standing randomly in a baseball field. For ease of argument, imagine both the number of pitchers and the size of the size of the field are infinite.
Okay, at a given signal, each throws a fastball at the head of the nearest pitcher and kills him. The question: After the throws, what portion of the pitchers will still be alive?
While this is not a hard problem, it will require a basic knowledge of calculus priniciples or at least pre-calculus elementary functions knowledge to solve it independently.