I’ve been out of school for decades, and I don’t spend my days solving equations (I’m more of a word person). Still, I like to think I have a solid grip on basic math: I can usually gauge whether a ...

She’s right—using simultaneous equations does get really complicated, and if you’d like to send me your work for the solution, I’d love to see it. But the system is also kind of a trick. Like a sudoku ...

There weren’t calculators or computers in medieval Europe. But there were math duels. Mathematicians would gather in public squares and pose tricky math problems to each other. Then they raced to ...