Order of Operations

We have reviewed Order of Operations in class and I have previously written about it in a blog but I have decided to dedicate one post to it prior to this test.

Order of Operations is the standard, accepted method for evaluating expressions and equations.  Order of Operations goes like this:

Parentheses
Exponents
Multiplication or
Division (whichever comes first, left to right)
Addition or
Subtraction (whichever comes first, left to right)

Let's look at an example. (remember that the ^ means an exponent)

2^3 + 9 (6 - 4) ÷ 2

The parentheses would have to be expressed first so we would rewrite the expression changing only what was inside the parentheses.

2^3 + 9 (2) ÷ 2.

Now, the (2) means to multiply, so we would not do that next.  We would, however, express the exponent.
2^3 = 2 x 2 x 2 = 8, so when we rewrite the expression it would be

8 + 9 (2) ÷ 2

Multiplication would come next, so we would multiply 9 and 2

8 + 18 ÷ 2

Division would come next and 18 divided by 2 would have use rewrite the expression

8 + 9

With addition left, we add 8 + 9 and our answer would be

17.

Step by step would look like this:

2^3 + 9 (6 - 4) ÷ 2
    8 + 9 (2) ÷ 2
       8 + 18 ÷ 2
         8 + 9
            17

I call this in class the upside down pyramid and I prefer students doing it this way because it shows each and every step and it is organized.

Use this link to find order of operation problems.

http://www.math-drills.com/orderofoperations/ooo_integers_foursteps_positive_pemdas_all.html