When performing a series of arithmetic operations (i.e. addition, subtraction, division, multiplication, exponents), you must perform those operations in a particular order. There is a mnemonic to help you remember the order – PEMDAS:
P | Parentheses |
E | Exponents |
M | Multiplication |
D | Division |
A | Addition |
S | Subtraction |
If you have a series of operations, do what’s in parentheses first, then apply exponents, then do any multiplication or division, and finally do any adding or subtracting.
Example:
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Do what’s in parentheses first (find LCD):
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So now we have
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Now apply exponents:
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So now we have
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So now we have

Now do addition and subtraction (find LCD):
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So our answer is
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Take Order of Arithmetic Operations Assessment
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