Keyword Search
Quick Order

Lesson ID: 183

# PEMDAS: Order of Operations

Mathematics, Algebra and Function, Operations (+, -, x, /, etc.), Problem Solving

## Objective

Students learn about the order of operations.

## Directions

In algebra, there is a specific order in which operations are performed when evaluating an expression or solving equations.
This is the algebraic order of operations:
1. Do any work within parentheses ( ) or other grouping symbols [ ] first.
2. Do any work with exponents (powers) or roots.
3. Do any multiplication or division in order from left to right.
4. Do any addition and subtraction in order from left to right.
The acronym for this order of operations is PEMDAS.
 Parentheses Exponents Multiplication Division Addition Subtraction

A popular expression for remembering this is: Please Excuse My Dear Aunt Sally.
Sample A
42 + (9 - 3) = ?
Do the work in the parentheses first.
42 + 6 = ?
Do the exponents next.
42 = 4 x 4 = 16, so16 + 6 = ?
Finally, add the numbers together.
16 + 6 = 22
42 + (9 - 3) = 22
Sample B
52 - (4 x 3) + 9 / 3 x 4 = ?
Do work in the parentheses first.
52 - 12 + 9 / 3 x 4 = ?
Do exponents next.
52 = 5 x 5 = 25, so25 - 12 + 9 / 3 x 4 = ?
Multiply and divide in order from left to right.
25 - 12 + 3 x 4 = ?
9 divided by 3 is 3, and 3 times 4 equals 12.
25 - 12 + 12 = ?
Add and subtract in order from left to right.
13 + 12 = ?
25 minus 12 is 13 and 13 plus 12 equals 25.
13 + 12 = 25