Why do buses come in threes?

""Deals in a very entertaining way with problems in normal life related to mathematics, luck, coincidence, gambling."" ? The Independent (London). Why do your chances of winning the lottery increase if you buy your ticket on Friday? Why do traffic lights always seem to be red when you?re in a hurry? read more

Suppose that buses leave the depot every fifteen minutes, but by the time they reach your stop, the buses are bunched in threes. For the sake of argument, let’s also say that the three buses in a bunch are only a minute apart. read more