Flipping through a deck of cards in the library as her friends and classmates slough through books and papers means that, sometimes, people want answers from Carolyn Chen. "I usually have to reassure ...

You know that sinking feeling. You've worked through the practice problems, reviewed your notes, and felt confident while studying. But the moment the exam paper hits your desk, the formula you swore ...

Start with a deck of cards. Before the trick, sneak a peek at the 10th card in the deck. Memorize it. Ask your volunteer to add the first and second digit of their number together. For instance, if he ...

You probably haven’t had to do longhand math in years, but you do mental math every day. Or maybe you google math problems ten times a day, because you’ve forgotten how to do any math beyond your ...

Add Yahoo as a preferred source to see more of our stories on Google. Math shouldn’t be harder than finding the last matching sock in your laundry. These clever shortcuts convert head-scratching ...

One of my fellow contributors here recently wrote a post about leap years and why we have them. This reminded me of modular arithmetic and the formula for calculating the day of the week for any date ...