When you flip a coin to make a decision, there's an equal chance of getting heads and tails. What if you flipped two coins repeatedly, so that one option would win as soon as two heads showed up in a ...

Welcome to The Riddler. Every week, I offer up problems related to the things we hold dear around here: math, logic and probability. There are two types: Riddler Express for those of you who want ...

When Bob flips a coin and announces the result, what can we really know about which coin he chose? This video builds probability trees to reveal how new evidence systematically updates our beliefs, ...