It seems that each student interpreted the problem differently, resulting in two different answers. Student 1 performed the operation of addition first, then multiplication; whereas student 2 performed multiplication first, then addition. When performing arithmetic operations there can be only one correct answer. We need a set of rules in order to avoid this kind of confusion. Mathematicians have devised a standard order of operations for calculations involving more than one arithmetic operation.

**Rule 1: First perform any calculations inside parentheses. **

Rule 2: Next perform all multiplications and divisions, working from left to right.

Rule 3: Lastly, perform all additions and subtractions, working from left to right.

The above problem was solved correctly by Student 2 since she followed Rules 2 and 3. Let's look at some examples of solving arithmetic expressions using these rules.

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Quoting: **WD** "Inside Parentheses" is what they first teach elementary school children. You learn how to really handle parentheses when you get older, by Distribution:

"We use the distributive property to help us find a way around the order of operations while still being sure that we keep the value of the expression."

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link to en.wikibooks.org]

Distribute BEFORE "pedmas" AND use with numbers, possible used to REMOVE parentheses too. [

link to www.algebra.com]

Get Rid of parentheses with Distribution:

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link to www.helpalgebra.com]

If there is some factor multiplying the parentheses, then the only way to get rid of the parentheses is to multiply using the distributive law.

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link to www.jamesbrennan.org]