1. Folded sheet of paper A rectangular sheet of paper is folded so that two diagonally opposite corners come together. If the crease formed is the same length as the longer side of the sheet, what is the ratio of the longer side of the sheet to the shorter side? Nick's Mathematical Puzzles: 1 to 10
Undergraduate contest problems and solutions
MathCaching GeoCaching Box #1 Welcome to the "GeoCaching" version of MathCaching! (This level is for Geometry students.) You are searching for 10 hidden internet boxes.
I came across a good brain teaser at this site: A fun card puzzle
NUMB3RS Episode 504: Thirty-Six Hours--Wolfram Research Math Notes