Order of Operations
Know what to solve first so mixed-operation expressions do not turn into guessing games.
Order of Operations
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Mixed operations have an agreed order
If you add first, you get 36. If you multiply first, you get 18. Only one can be correct.
P — Parentheses
E — Exponents
MD — Multiplication and Division from left to right
AS — Addition and Subtraction from left to right
Use P → E → MD → AS
- P — Parentheses: Do anything inside grouping symbols first.
- E — Exponents: Evaluate powers next. Example: 3² = 9.
- MD — Multiply or Divide: Work from left to right.
- AS — Add or Subtract: Work from left to right.
- CHECK: PEMDAS does not mean multiplication always comes before division, or addition always before subtraction.
Seven patterns you should recognize
1. Multiply before add
8 + 2 × 52 × 5 = 10, then 8 + 10 = 18.
2. Parentheses first
(8 + 2) × 58 + 2 = 10, then 10 × 5 = 50.
3. Exponents before multiplication
2 + 3² × 2Exponent first: 3² = 9.
Then multiply: 9 × 2 = 18.
Then add: 2 + 18 = 20.
4. Division before subtraction
30 − 18 ÷ 318 ÷ 3 = 6, then 30 − 6 = 24.
5. Multiplication and division: left to right
24 ÷ 6 × 224 ÷ 6 = 4, then 4 × 2 = 8.
6. Addition and subtraction: left to right
20 − 7 + 320 − 7 = 13, then 13 + 3 = 16.
7. More than one layer
5 + 2 × (9 − 6)Parentheses: 9 − 6 = 3.
Multiply: 2 × 3 = 6.
Add: 5 + 6 = 11.
What should we do first?
- There are no parentheses.
- Do division and multiplication before addition.
- From left to right: 18 ÷ 3 = 6.
- Then 4 × 2 = 8.
- Now add 6 + 8.
Watch out for these
Multiplication/division must happen before addition/subtraction.
They are equal priority. Go left to right.
Grouping changes the order completely.
Write one clean step at a time on harder items.
Build the skill
Work one operation at a time. These start direct and become more mixed.
Can you choose the first move fast?
Five short expressions. Keep the order straight.
Can you do it without hints?
Score 5/5 to verify this competency. If you miss one, a fresh set will be ready.
Still unsure what to solve first?
Send Teacher Abi the expression that confused you and your result. I can show you the quickest clean order.
Message Teacher AbiChoose your next step
Next competency: Integer and Signed-Number Reasoning
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