Counting will get you nowhere. Try a little combinatorics instead. By Kenneth Chang A couple of weeks ago, I wrote about a viral math problem — 8÷2(2+2) = ? — that drew the disdain of many ...

Everyone learns the number one rule about triangles in high school: the angles of a triangle add up to 180 degrees. But did you know that sometimes they don't? Triangles are much more interesting than ...