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 ...

The arrangement leaves gaps in the square’s four corners, two of which are filled with smaller circles that just barely touch ...

Here, count with me: 1, 2, 3, 4, 5, 6, 7, 8, 9, T, 11, 12 … Oh, what’s that? You write ten with “zero”? Fair enough. Zero, we have been told, is the ...

Exactly how many triangles can you count in this fun triangle puzzle?