For four game show variations of the hat puzzle, four clever ways to earn a better payoff than you might expect.

In three new variations of a famous logic puzzle, what are the best strategies for guessing the color of the hat on your head?

Assigning elements from a large collection to one of two categories can yield almost “magical” predictions about highly complicated problems without actually solving them.

In a geometrically designed social club, how do dancing, triangles and hexagons mix?

The solution to this month’s puzzle gets to the bottom of the famously ambiguous Sleeping Beauty probability problem.

Like a visually ambiguous Necker cube, the famous Sleeping Beauty problem can be perceived in two seemingly valid ways.

The solution to this month’s puzzle explains how to design a Sudoku square to figure out the likes and dislikes of four or eight finicky friends.

For this month’s puzzle, design a Sudoku square to figure out the likes and dislikes of four finicky friends.

The solution to this month’s puzzle explains how to find a rule behind a given sequence of numbers and challenges readers to take on a ‘lovely’ unsolved problem.