Order of Operations

Contributor: Alison Weiss. Lesson ID: 10617

5 + (14 + 3) x 2 - 9 Whoa! How do you solve that problem? It's simple once you know the trick! Complete these online activities to learn the order of operations to solve every math problem.

categories

Arithmetic, Operations and Algebraic Thinking

subject
Math
learning style
Auditory, Visual
personality style
Lion, Beaver
Grade Level
Intermediate (3-5)
Lesson Type
Quick Query

Lesson Plan - Get It!

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5 + (14 + 3) x 2 - 9

  • Whoa! How do you solve that problem?

It's simple once you know the trick! 

Here's a hint: Please Excuse My Dear Aunt Sally!

The order of operations are important for more than just complicated math problems like the one above!

This method to solving math statements really comes from a place where everyone needs to solve a problem the same way or else everyone will not get the same answer.

That sounds confusing too! But, let's prove it.

  • If your teacher puts this problem on the board, how would you solve it?
  • How would the student next to you solve it?

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You may simply solve the problem from left to right.

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But your friend may look at the problem and notice 2 x 10 is easy, so she'll do that part first.

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There are two different answers!

  • How do we know which way is correct?

If only there were some sort of rule for everyone to follow!

There is! It's the Order of Operations!

This is the order everyone follows in math to solve for the correct answers!

order of operations

To help remember this rule, you can make an acronym using the first letters of each operation.

This makes PEMDAS and can be remembered by the saying Please Excuse My Dear Aunt Sally.

Now that you know the order of operations, let's look back at the first problem.

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There are no parentheses or exponents, so you can skip those steps.

Looking at PEMDAS, the next step is multiplication. So we will do that operation first.

The next operation is addition. So, we will do that last while solving our problem.

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Now, let's look at a harder problem!

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Remembering PEMDAS, we know that parentheses are the first step in the order of operations. We will solve that step first.

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The operations we have left in this math statement are multiplication and subtraction.

  • Which should we do next?

If you thought, multiplication; you are right! You are beginning to understand PEMDAS!

The last step to solve this problem is subtraction!

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Great! You are ready to practice solving more math statements using the order of operations! Visit the Got It? section to try some problems on your own!

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