1-4: Order of Operations

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M S G E D

LEFT TO RIGHT

A

P: ( ) [ ] E: exponents M: x D: A: + S:

k

Order of Operations

Where do I start?

14 You

evaluate

an expression by finding its value..."working the problem" Jack and Jill were asked to evaluate the expression

3 + 4 x 2

and got different answers! 11

Jack explained how he got his answer....

3 + 4 x 2 = 7 x 2 = 14

Jill explained how she got her answer....

3 + 4 x 2 = 3 + 8 = 11

To make sure everyone gets the same results, mathematicians have agreed on a set of rules called the

order of operations

.

Let's solve numeric expressions!

Pull or click the arrows to learn about my trip here and the Order of Operations Pull Me!

Paralleled Please Evaded enraged Excuse trees and divides as they appeared My Dear and army ants Aunt Sally 3 For Looking Too Rough From Left To Right

These bars look like parenthesis! Take care of whatever is inside of these first, then set the problem back up. There may be more than one set in an expression.

23 + (6-3) x 4 ÷ 2+8= 23 + 3 x 4 ÷ 2+8=

Aunt Sally to the Elephant power!

Next, simplify any exponents (powers) in the expression by performing repeated multiplication. The tiny number tells you how many times a number is multiplied by itself.

23 + (6-3) x 4 ÷ 2+8= 23 + 3 x 4 ÷ 2+8= 2 x 2 x 2 8 + 3 x 4 ÷ 2+8= Click here!

3

Then, divide or multiply from left to right. Solve one problem before answering the next!

23 + (6-3) x 4 ÷ 2+8= 23 + 3 x 4 ÷ 2+8= 8 + 3 x 4 ÷ 2+8= 8 + 12 ÷ 2 +8= 8 + 6 +8=

Finally, subtract and add any remaining facts as they appear from left to right.

23 + (6-3) x 4 ÷ 2+8= 23 + 3 x 4 ÷ 2+8= 8 + 3 x 4 ÷ 2+8= 8 + 12 ÷ 2 +8= 8 + 6 +8= 8 + 6 + 8= 14 + 8= = 22 From Left To Right Will lead you to the correct answer!

14 Jack and Jill were asked to evaluate the expression

3 + 4 x 2

11 So, who was right?

What Does PEMDAS stand for?

P arenthesis E xponents M ultiplication D ivision A ddition S ubtraction

Explore...

Drag the step into the table to work your way through the end of each row to reveal the value of the expression.

expression 1st operation 2nd operation 3rd operation value 10 -3 x 2 4 x 32 (8 -5) x 23 add or subtract multiply or divide multiply or divide evaluate inside parentheses evaluate inside parentheses add or subtract multiply or divide multiply or divide 4 36 24 evaluate powers

Solve these expressions using the rules we just learned. How did order affect the results?

144 - (7 x 12) = 144 60 84 = (7 x 12) + 144 = 84 + 144 = 228 Pull Please Excuse 3 (144 - 7) x 12 = 137 x 12 = 1644 My 7 + 144 x 12 = 7 + 1728 = 1735 Aunt Dear Sally

Practice Questions 1. 32 + 4 3. (3x5) + (6/2) 18 4. 22 + 5 x 2 14 13 6. 3 x (22 + 1) 15 7. (8 - 3 ) x 2 + 10 20 8. (5-1)2 + 4 -2 x 1 18 9. 10 / 5 - 2 + 10 10 10. (52 + 4) - 10 19

Ch 1-4

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