You may never have heard of modular arithmetic, but you use it every day without the slightest difficulty. In this system, numbers wrap around when they reach a certain size called the modulus; it ...

Everyone knows that arithmetic is true: 2 + 2 = 4. But surprisingly, we don’t know why it’s true.. By stepping outside the box of our usual way of thinking about numbers, my colleagues and I ...

Barbie caught a lot of flack back in the ’90s for declaring, “Math class is tough!” Today we find ourselves in the disorienting position of defending her. We recently got a note f… ...