Clearly you do not share the distinction of a 4.0 GPA. Try re-reading and see if you can discern a central theme or two. Hint: it has nothing to do with Minnesota or drinking water at night.

If you are a determined to be snarky, you might fixate on the fact that the girl's mother is confused about fractions, since two fractions may have common denominators or different ones, but not "different common denominators." Still, even that is not much of a club to wield. After all, despite the mother's apparent lack of mastery, all indicators are that the daughter has a solid grip on math that probably far exceeds your own.