We live in a world where a lot of things seem to happen by pure chance, from winning the Lotto to losing your car keys. But the truth is, the likelihood of many everyday things happening is heavily ...

Forbes contributors publish independent expert analyses and insights. Writes about the future of finance and technology, follow for more. Joint probability teaches us to calculate combined outcomes.

IT may possibly be of some little interest to notice that the theorem in probability, which goes by the name of James Bernoulli's theorem, alluded to in my letter to NATURE of December 13, 1900 (p.