There are two basic ways to do fractions on your iPhone calculator. Here's what you need to know to use the built-in app.

There are two rules to remember when adding or subtracting fractions. The fractions need to have a common denominator. This means the denominator has to be the same. You only need to add or subtract ...

We know there are individual differences in math ability, even at a young age, but what basic cognitive tools lay the foundation for whether we are good with numbers? And specifically, what basic ...