GOOD AFTERNOON! Today we will be learning about the "Order of Operations".

Transcription

1 GOOD AFTERNOON! Today we will be learning about the "Order of Operations". Let's do a few practice problems before we get started. 1) 8 * 36 = 2) = 3) 29 * 5 = 4) 42 3 =

2 Let's review what we covered the last time we met! Remember that we can write 2 * 2 * 2 using an exponent and find its value. base exponent 2 3 = 8 In words, we say "two to the third power" OR "two cubed".

3 4 2 = 4 * 4 = 16 In words, we say "four to the second power" OR "four squared". How would we write 3 4 power using an exponent? What is the value of 3 4?

4 We can also write Prime Factorization using exponents * VERY GOOD!! ARE YOU READY TO CONTINUE WITH TODAY'S LESSON?

5 A Numerical Expression is a combination of numbers and operations. Examples: * (10 * 8) - 7

6 Do you know what we mean by "Operations"? We "operate" on the numbers by 5 9 Adding Dividing x + Subtracting 2 Multiplying

7 How might you solve this problem? * 5 Could another student solve this problem differently? * 5 How do we know which one is correct?????

8 To find the correct answer, we need to follow an Order of Operations This tells us which operation to perform first so that everyone gets the same final answer!

9 Order of Operations P E M D A S 1. Parentheses 2. Exponents 3. Multiplication Division 4. Addition Subtraction Simplifying the expressions inside grouping symbols examples: (3+5) or (4*6) Find the value of all powers examples: 2 3 or 4 2 Perform multiplication or division in the order in which it occurs when reading the expression from left to right. Perform addition or subtraction in the order in which it occurs when reading the expression from left to right.

10 We can remember the Order of Operations as PEMDAS P E M D A S xponents ubtraction ddition ivision ultiplication arentheses "Please Excuse My Dear Aunt Sally"

11 Or P E M D A S ddition ivision ultiplication xponents ubtraction arentheses "Purple Eggplants Make Delicious Afternoon Snacks!"

12 Let's try some... P E M D A S arentheses xponents whichever comes first ultiplication ivision whichever comes first ddition ubtraction numerical expression * 5 = Read from left to right... just like a book. There are no Parentheses. There are no Exponents. There is some Multiplication so do this first = We perform the Addition last. 19

13 "Purple Eggplants Make Delicious Afternoon Snacks!" P E M D A S arentheses xponents whichever comes first whichever comes first ultiplication ivision ddition ubtraction Read the expression from left to right = = We perform Addition and Subtraction in the order in which they occur. So do the Subtraction first! Then do the Addition. 16

14 P E M D A S arentheses "Please Excuse My Dear Aunt Sally" xponents whichever comes first ultiplication ivision whichever comes first ddition ubtraction * (9-6) = * 3 = * 3 = = Do the operations in Parentheses first. There are no Exponents. Perform Multiplication or Division in the order in which they occur. The Division should be done first. Then perform the Multiplication. Finally perform the Addition. 56

15 P E M a) x 15 = Your turn! b) 10 + (6-5) = D A c) 25 x (5-2) 5 = d) = S

16 Sometimes we have operations "nested" within the parentheses which must be completed first. Example: 60 ( ) x 9 = 60 (12 + 8) x 9 = x 9 = 3 x 9 = We want to do the Parentheses but first we must take care of the Exponents WITHIN the Parentheses. Then we can solve the Parentheses. Division comes before Multiplication when reading the expression from left to right. Finally we can perform the Multiplication. 27

17 Practice Problems 1) = 2) = 3) (26 + 5) x 2-15 = 4) 5 + (21-3) = 5) 18 (2 + 7) x = 6) 21 (3 + 4) x 3-8 = 7) = 8) 19 - ( ) + 6 =

18 Good Job!!!! Let's take a break!

19 LET'S PLAY! Roll the dice and generate 5 numbers between 1 and 12. Use the 5 numbers to create a "Numerical Expression"and then simplify. Use Parentheses, Exponents, Multiplication, Division, Subtraction and/or Addition.

20 What is the value of 100 divided by 5 times 4 minus 79? (Can you write this out as a "Numerical Expression"?)

21 Can you develop an expression that uses multiplication, division, addition, and subtraction, as well as grouping symbols, whose solution is 2?????

22 Adult admission to a football game is $5, and student admission is $2. Which expression could be used to find the total cost of 2 adult and 4 student admissions to the football game? a.) 2 + $5 x 4 + $2 b.) $5 + $2 + 6 c.) $2 + 4 x $5 + 2 d.) 2 x $5 + 4 x $2

23 1.) Can you give me an example of a "Numerical Expression"? 2.) What do I mean by "Operations"? 3.) In what order do I perform the "Operations"? 4.) Find the value of each expression? a.) 5 x 6 - (9-4) = b.) x 3 = c.) = d.) x 3 = e.) (8 + 1) x =

24 You did a GREAT job today!!! * We learned to identify a "Numerical Expression". 4 + (8 x 2) - 3 * We learned about "Operations". + - x * We learned that we need to perform "Operations" in a certain order. P E M D A S Parentheses Exponents Multiplication Division Addition Subtraction * We learned some funny ways to remember the "Order of Operations". Please Excuse My Dear Aunt Sally! Purple Eggplants Make Delicious Afternoon Snacks!