PEMDAS – The American Version of Order of Operations
๐ PEMDAS – The American Version of Order of Operations
PEMDAS is the U.S./North American mnemonic for the same mathematical rule known elsewhere as BODMAS (India/UK/Australia) or BOD (simplified form).
Though the names differ, the principle remains universal — a disciplined order to keep our calculations honest and consistent.
๐ค PEMDAS Full Form
Letter
Meaning
Operations
P
Parentheses
( ) → Brackets
E
Exponents
x², √x, x³ → Orders
MD
Multiplication & Division
× and ÷ → left to right
AS
Addition & Subtraction
+ and − → left to right
Key: M and D share equal priority → perform left to right.
A and S share equal priority → perform left to right.
๐ PEMDAS vs BODMAS vs BOD
Mnemonic
Region
Key Difference
PEMDAS
USA, Canada
Parentheses → Exponents → MD/AS
BODMAS
India, UK, Australia
Brackets → Orders → DM/AS
BOD
UK (simplified)
Brackets → Orders → D/M → A/S
All give the same answer — only the words differ!
๐งฎ Worked Examples Using PEMDAS
Example 1: 12 ÷ 3 × 4
Left to right: 12 ÷ 3 = 4 → 4 × 4 = 16
Answer: 16
Example 2: (8 + 2) × 3 − 4 ÷ 2
P: (8 + 2) = 10
MD: 10 × 3 = 30, 4 ÷ 2 = 2
AS: 30 − 2 = 28
Answer: 28
Example 3: 2 + 6 ÷ 2 × 3 − 1
MD: 6 ÷ 2 = 3 → 3 × 3 = 9
AS: 2 + 9 = 11 → 11 − 1 = 10
Answer: 10
Example 4: 5 × (4 + 3)² ÷ 7
P: (4 + 3) = 7
E: 7² = 49
MD: 5 × 49 = 245 → 245 ÷ 7 = 35
Answer: 35
⚠️ Common PEMDAS Mistakes (and Fixes)
Mistake
Expression
Wrong Answer
Correct
Doing M before D
12 ÷ 3 × 4
1
16
Forgetting left to right
20 − 3 × 4 + 2
6
10
Treating PEMDAS as strict order
10 ÷ 2 × 5
1
25
๐ก PEMDAS Mnemonic Tip
Letter
Fun Phrase
P
Please
E
Excuse
M
My
D
Dear
A
Aunt
S
Sally
"Please Excuse My Dear Aunt Sally" — a friendly way to remember the order that keeps math neat and fair.
๐ PEMDAS vs BODMAS: Side-by-Side
Expression
PEMDAS Steps
BODMAS Steps
Answer
10 − 2 × 3
M: 2×3=6 → S: 10−6=4
M: 2×3=6 → S: 10−6=4
4
18 ÷ 3 × 2
18 ÷ 3 = 6 → 6 × 2 = 12
18 ÷ 3 = 6 → 6 × 2 = 12
12
๐ Final Summary Table
Rule
Region
Order
PEMDAS
USA
P → E → M/D (←) → A/S (←)
BODMAS
India/UK
B → O → D/M (←) → A/S (←)
BOD
UK (simple)
B → O → D/M → A/S
MAS
Partial (unsafe alone)
Only M → A → S
Golden Rule: When operations share priority, always go left to right.
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