Primary Mathematics/Quick Reference/Operator Precedence

This table shows the precedence of primary mathematics operators.

As a simple example, 1+2×3 = 7 not 9 because the multiplication is performed before the addition, superseding the left to right convention. Also, 3 + 52 = 28 and 3 × 52 = 75 because of the precedence of exponentiation over multiplication.

The mnemonic PEMDAS can help to remember this. This can be expanded to “Please Excuse My Dear Aunt Sally.”

For a complete discussion, please see the Wikipedia article on order of operations.