1. Order of Operations By Mr. Walker

2. The Expression We need to simplify this expression down to one number (find the answer). But where do we start? There is a certain order we need to follow when we simplify this expression, or we will get the wrong answer. This is called… Order of Operations It goes like this…Going left to right (like when reading) Do anything in Parentheses Start over and do any Exponents Start over and do any Multiplication and Division Start over and do any Addition and Subtraction +(3x5)-2 3 25 5

3. Definitions +(3x5)-2 3 25 5 Parentheses are… Exponents are …Powers and Roots 2 16 In this problem 2 has a power of three, which means you should multiply 2 by itself three times: 2x2x2 Multiplication and Division are … ( ) X is the same as saying 25 5 25 5 Addition and Subtraction are… + - 3

4. How Do I Remember All This? Easy…Please Excuse My Dear Aunt Sally ParenthesesParentheses ExponentsExponents MultiplicatonMultiplicaton DivisionDivision AdditionAddition SubtractionSubtraction Dear Aunt Sally had a very bad day, so please excuse her. It all started when she burnt her tongue on her hot coffee. Then on the way to work her car died. While she was walking the rest of the way to work a car drove by and splattered her with mud. When she finally got to work her boss fired her for being late. Since she did not have a job anymore she started walking home and found a quarter on the sidewalk near a tree. ‘Great,’ she thought but soon found out that it was super-glued to the sidewalk. While she was looking down at the quarter a bee stung her and she stood up so fast that she forgot the tree branch right above her head. BONK! Just then a 7 year old boy bumped into her because he was reading a comic book as he walked. When he looked up to say ‘Excuse me,’ this is what he saw… So …Please Excuse My Dear Aunt Sally

5. Step by Step ‘P’ +(3x5)-2 3 25 5 Please Excuse My Dear Aunt Sally ParenthesesParentheses (3x5) is 15, so put the 15 in the spot of the (3x5) +15-2 3 25 5

6. Step by Step ‘E’ Please Excuse My Dear Aunt Sally ExponentsExponents +15-2 3 25 5 2Is the same as 2x2x2 2x2=4 x2 again is 8 So replace the 2 with the 8 3 3 +15-8 25 5 You most likely will not have to deal with this step in 4 th grade.

7. Step by Step ‘M’ & ‘D’ Please Excuse (My Dear) Aunt Sally MultiplicatonMultiplicaton +15-8 25 5 There is nothing to multiply so do the division. DivisionDivision +15-8 25 5 is the same as saying 25 5 25 5 25 divided by 5 is 5. So replace the with the 5 25 5 5+15-8 Do any multiplication and division as you read left to right

8. Step by Step ‘A’ & ‘S’ Please Excuse My Dear (Aunt Sally) AdditionAddition 5+15-8 Add the 5+15 to get 20 Take out the 5+15 and put the 20 in that spot 20-8 SubtractionSubtraction Subtract the 8 from the 20 and get 12 20 - 8 12 1 10 Take away the 20-8 and put the 12 borrow Do any addition and subtraction as you read left to right 12 You are done!

9. Let’s Try One Together Remember Please Excuse My Dear Aunt Sally 36 6 5+(3x4)- Parentheses: (3x4) = 12 Exponents: None-Skip Multiplication: None-Skip Division: 36 divided by 6 = 6 Addition: 5+12=17 Subtraction: 17-6=11 36 6 5+12- 36 6 5+12- 36 6 5+12- 5+12-6 17-6 11 Simplify this expression

10. Try These On Your Own 50 5 2+(4x9)- Answer 28 4x(1+7)-24 3 Answer 24 56 7 +2x(3x9)-60 Answer 2 45 9 3 -20+( +5)-7 Answer 10 3

11. For Fun Make Up Your Own Aunt Sally Story Please Excuse My Dear Aunt Sally because…