The rules of Sudoku dictate that every row, column and 3×3 bolded box in the completed grid must contain the digits 1 through 9 exactly once. A surprising fact emerges from these simple rules. In ...

It's a math puzzle designed for third graders, but many adults are having trouble solving it. The puzzle looks something like Scrabble, with a series of boxes that snake up, down and across a page.

[Kagen Sound] is a woodworker and artist who gives a great behind-the-scenes look at his amazingly high-quality puzzle boxes (video). Not only do his varied puzzle box designs show his math background ...

A classic puzzle conundrum goes like this: You’re in a room with two ropes and a box of matches. Each rope takes exactly an hour to burn all the way across, but it might burn faster through some ...