To add -4 and 5, draw the starting number on a number line and count to the right when adding numbers. What is the difference in temperature between a desert at 40 °C and a mountain top at -2 °C? \(40 ...

To add and subtract numbers always begin counting from zero. When adding positive numbers, count to the right. When subtracting positive numbers, count to the left.

When you add or subtract currency-formatted numbers, Excel 2013 automatically adopts the currency format for the results. Adding and subtracting figures follows similar procedures, but you must be ...

Young children can crudely add and subtract numbers before they have learned the rules of arithmetic, a new study finds. Researchers presented five- and six-year-old children with problems such as, ...