When you have more than one operator in an arithmetic expression, the order of numbers and operators can be critical. For example, in the following expression, which operation does the language processor perform first?

7 + 2 * (9 / 3) - 1

Proceeding from left to right, it is evaluated as follows:

• Expressions within parentheses are evaluated first.
• Expressions with operators of higher priority are evaluated before expressions with operators of lower priority.

Thus the preceding example would be evaluated in the following order:

1. Expression in parentheses

   7 + 2 * (9 / 3) - 1
            \___/
              3

2. Multiplication

   7 + 2 * 3 - 1
       \___/
         6

3. Addition and subtraction from left to right

   7 + 6 - 1 = 12