Animal psychologists have found that giraffes can mentally combine small sums of objects, but can't perform the subtractive equivalent.

In addition to humans, some species of primates and birds have demonstrated under experimental conditions their ability to ...

Students put all of their addition and subtraction skills together to solve equations. In this lesson, students put all of their addition and subtraction skills together to solve equations. Julia ...

Here you will find a video about addition and subtraction. Watch this, and then test your knowledge with a short quiz before exploring the rest of the collection. This section contains videos from our ...