I just finished taking the Putnam examination, a college math competition that lasts a whole day. There are two parts, and each part has 6 questions that you complete in 3 hours. Each question is graded out of 10, so there are a maximum of 120 points. The median score is usually 1-2 out of 120, but this time (at least the person running the competition told me) it could be as high as 10 because there were a couple problems that were really easy.
Anyway, this is as good a time as any to start a new feature of the blog: "RPG Math," a series of math problems based on actual scenarios from role-playing games.
Problem 1: Ineligible Receiver (of bullets) Downfield
In the tabletop wargame "Necromunda" (as well as several other similar games) a unit is only allowed to shoot at the closest enemy unit to him. (The game is played on a tabletop; there is no grid or 'game board' of any kind, and rulers are used for measuring distances.) Describe a simple way of determining which of two enemy units is closest to a particular friendly unit without actually measuring any distances. (You may use a compass and straightedge.)
Here is the solution.