Order of Operations

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How do you know what to do first in this expression?
2 × 3 + 3 = x
Maybe it’s addition first, then multiplication. Adding first gets you . . .
2 × 3 + 3 = 12 WRONG!
Or, maybe it’s multiplication first, then addition. Multiplying first gets you . . .
2 × 3 + 3 = 9 Right!
And then you set fire to your math book before it gets more complicated, like . . .
7 + (2 × 32 + 3) = x
Learn this word to help you:
PEMDAS: Parentheses, Exponents, Multiplication/Division, Addition/Subtraction
Perform the operations in parentheses first. Of course, that means you have to do other operations. Start with exponents.
7 + (2 × 32 + 3) = x
7 + (2 × 9 + 3) = x
Then multiplication/division
7 + (18 + 3) = x
Then addition/subtraction
7 + (21) = x
Finally, add the parentheses to the remainder of the expression.
28 = x

Most importantly, remember Exponents, Multiplication/Division, Addition/Subtraction

  • 2 × 3 + 3 =
    2 × 3 + 3 = 9
  • 2 + 3 × 3 =
    2 + 3 × 3 = 11
  • 3 × 4 + 2 =
    3 × 4 + 2 = 14
  • 3 + 4 × 2 =
    3 + 4 × 2 = 11
  • 2 + 32 × 2 =
    2 + 32 × 2 = 20
  • 32 × 2 - 2 =
    32 × 2 - 2 = 16
You may have heard that you should go from left to right. This is true within multiplication/division, for example.
12 ÷ 3 × 4 = 16 Right!
If you go right to left, you get
12 ÷ 3 × 4 = 1 WRONG!