Order Of Operations

What Is PEMDAS?

PEMDAS is a "MNEMONIC" ("NEW-MON-NIC"). of Order Of Operations. Addition, subtraction, multiplication, division, and raising number to a power must be performed in a specific order to get the correct answer. For example, expressions enclosed in parentheses are evaluated first. Here is the order that must be followed - PEMDAS:

• Parentheses
• Exponents
• Multiplication and Division (left to right)
• Addition And Subtraction (left to right)

It is used to help us remember the order each operation is applied to a Arithmetic equation. Before reading this page, it is recommended the reader read the following pages for a more complete understanding of the subject: Equality and Inequality, Math Symbols.

• Parentheses ( and ) are used in mathematical expressions to indicate order of math operations (precedence rules). In a math statement like (3+5)×7, the part of the expression within the parentheses, (3+5)=8, is evaluated first, and then this result is used in the rest of the expression. Nested parentheses work similarly, the inner most expression is evaluated first.
  
• Exponents (^) are evaluated second in equation. If an exponent is in a parentheses, it is processed first. The exponent of a number says how many times to use that number in a multiplication problem. It is written as a small number to the right and above the base number. For example: 2³ = 2 × 2 x 2 = 8, or shown another way 2^3 = 2 x 2 x 2 = 8.
  
• Multiplication (× or *)
  Division       (÷ or /) Multiplication and Division are processed left to right after exponents are evaluated.
  
• Addition    (+)
  Subtraction (-) Addition and Subtraction are processed last left to right after Multiplication and Division.
  

Let's step back for a moment. There is a easier way to remember PEMDAS. Remember its is a MNEMONIC that can be expanded into an easy to remember phase: "Please Excuse My Dear Aunt Sally".