Over the course of centuries, a calendar with no leap years would eventually become totally out of sync with the seasons as we know them. Let’s see what would happen. Leap years exist because we need ...

Randomly scramble the digits 0, 1, 2, 3, 4, 5 and 6 to form a seven-digit number (or a six-digit number if the leading digit is 0). Rank the following events in order ...

When I was a little kid I had a friend who was born on February 29, the “leap day” we add to that month every four years. I remember we used to tease him by saying that he was only three years old. I ...

"American society today is hardly recognizable from what it was a century ago. Integrated schools, an information economy, and independently successful women are but a few of the remarkable changes ...