Divide a group of people into two disjoint subgroups (of arbitrary size) such that the difference in the total ages of the members of the two subgroups is as large as possible.

Reword the question below so it's less ambiguous so I can understand the question and answer it on my own.  maybe give example diagram/inputs/outputs (primitives if possible) but don't show any algorithms in the answer. I know big theta notation/sorting algorithms etc..  This question has been answered at brainmass but I don't want the answer just the question being less ambiguous to me.

Question:
Sometimes a slight change in a problem can significantly alter the form of its solution.  For example, find a simple algorithm for solving the following problem and classify it using big-theta notation:

Divide a group of people into two disjoint subgroups (of arbitrary size) such that the difference in the total ages of the members of the two subgroups is as large as possible.