Home

Algebra and Pre-Algebra Lessons

Algebra 1 | Pre-Algebra | Practice Tests | Algebra Readiness Test

Algebra E-Course and Homework Information

Algebra E-course Info | Log In to Algebra E-course | Homework Calculator

Formulas and Cheat Sheets

Formulas | Algebra Cheat Sheets
» » Order of Operations

Using the Order of Operations - Also Known as PEMDAS

How many times have you evaluated a numerical expression, and even though you know your addition, subtraction, multiplication, and division is correct, you still have the wrong answer?

If this has happened to you, then you probably haven't used the Order of Operations correctly.

What is the Order of Operations?

The order of operations is a set of rules that you must follow in order to correctly evaluate a numerical expression that contains multiple operations (a combination of addition, subtraction, multiplication, and division).



The Order of Operations

In order to evaluate an expression with more than one operation, you must:

  • 1. Evaluate expressions inside of grouping symbols (parenthesis or brackets).

  • 2. Evaluate powers (think exponents).

  • 3. Multiply and/or divide from left to right.

  • 4. Add and/or subtract from left to right.


In order to remember this set of rules, many people remember the acronym, PEMDAS. Check it out:

PEMDAS

Ok, now let's use this set of rules to evaluate numerical expressions.



Example 1

Order of Operations Example



Tip

If you find that you are having trouble, use colored pencils to help color code your work as I have done in the example above.

This will help you to organize your work and make sure that you follow the rules correctly.

Many people get confused because you may start computing in the middle of the numerical expression.

You can color code by underlining the part of the problem that you are focusing on. Take a look at Example 2.



Example 2

Order of Operations Example


One last example with a power to evaluate. Take a look....

order of operations example


We will continue our study of the order of operations in our next lesson, as we focus on alternative grouping symbols.



More Pre-Algebra Lessons You Might Like



Like This Page?



Comments

We would love to hear what you have to say about this page!


Top of the Page

Connect and Follow Algebra Class



Copyright © 2009-2015 Karin Hutchinson ALL RIGHTS RESERVED