Transcript order of operations practice ppt

Think about this…
•What would happen if there
were no rules for driving?
•What would happen if there
were no rules for solving math
problems?
What’s wrong?
•Look at both of the problems.
•Notice the difference in the way they
are solved.
•Which one do you think is correct?
48  6  2
 8 2
 16
48  6  2
 48  12
4
3
4
-
Order of 
Operations
()
+
X
The Order of Operations
tells us how to do a math
problem with more than one
operation, in the correct
order.
Please Excuse My Dear Aunt Sally
This will
help you to
remember
the order of
operations.
Please Excuse My Dear Aunt Sally
P
E
M
D
A
S
Parentheses ( )
Exponents
Multiply x
Divide 
Add +
Subtract -
3
4
Please Excuse My Dear Aunt Sally
Parentheses (
Always do
parentheses
1st.
)
Please Excuse My Dear Aunt Sally
Exponents
Always do
Exponents
2nd.
3
4
Please Excuse My Dear Aunt Sally
Multiply x
Divide 
Do
multiplication
and division
3rd, from left to
right.
Please Excuse My Dear Aunt Sally
Add +
Subtract Do addition and
subtraction 4th,
from left to right.
Let’s Try Some
 Problems!
PEMDAS
3
3+2 -
(9+1)
3
3+2 - 10
3+8-10
11-10
1
PEMDAS
2
6
3 (9+1) +
2
3(10)+6
3(10)+36
30+36
66
PEMDAS
4+5 x (6-2)
4+5 x 4
4+20
24
PEMDAS
3
2
4+ 10 x
-16
4+10 x 8 -16
4+ 80 -16
84-16
68
PEMDAS
21 +
 10
21+10010
21 + 10
2
10
31
PEMDAS
2
10+7 -2
x5
10+49–2 x 5
10+49- 10
59 - 10
49
Practice Problems
1. 3 + 5 x 7
2. (1 + 3)  (8 – 4)
3. 6 – 6 + (7 – 0) – 7
4. 4 – 3 + (5 – 1) – 3
5. 3 + 9  8 – 62
6. 24 ÷ 6  2  2 ÷ 4
7. 2 + 3  [4 + (6  3 – 8)]  2
Answers to Practice Problems
1. 3 + 5 x 7
3+57
3 + 35
38
2.
(1 + 3)  (8 – 4)
(1 + 3)  (8 – 4)
4  (8 – 4)
44
16
Answers to Practice Problems
3.
6 – 6 + (7 – 0) – 7
6 – 6 + (7 – 0) – 7
6–6+7–7
0+7–7
7–7
0
4.
4 – 3 + (5 – 1) – 3
4 – 3 + (5 – 1) – 3
4–3+4–3
1+4–3
5–3
2
Answers to Practice Problems
5. 3 + 9  8 – 62
6. 24 ÷ 6  2  2 ÷ 4
3 + 9  8 – 62
24 ÷ 6  2  2 ÷ 4
3 + 72 – 62
75 – 62
13
422÷4
82÷4
16 ÷ 4
4
Answers to Practice Problems
7. 2 + 3  [4 + (6  3 – 8)]  2
2 + 3  [4 + (6  3 – 8)]  2
2 + 3  [4 + (18 – 8)]  2
2 + 3  [4 + 10]  2
2 + 3  14  2
2 + 42  2
2 + 84
86
Websites
http://www.aplusmath.com/cgibin/Flashcards/Order_Of_Operations
http://www.funbrain.com/algebra/index.html
http://www.theteacherscorner.net/printable-worksheets/makeyour-own/math-worksheets/algebra/order-of-operations.php
http://www.teachnology.com/worksheets/math/order/
Example #1
14 ÷ 7 • 2 - 3
= 2 • 2 - 3 (Divide l/r.)
=4-3
(Multiply.)
=1
(Subtract.)
Example #2
3(3 + 7) 2 ÷ 5
= 3(10) 2 ÷ 5
(parentheses)
= 3(100) ÷ 5
(exponents)
= 300 ÷ 5
(multiplication)
= 60
(division)
Example #3
20 - 3 • 6 + 102 + (6 + 1) • 4
= 20 - 3 • 6 + 102 + (7) • 4
(parentheses)
= 20 - 3 • 6 + 100 + (7) • 4 (exponents)
= 20 - 18 + 100 + (7) • 4
(Multiply l/r.)
= 20 - 18 + 100 + 28
(Multiply l/r.)
= 2 + 100 + 28
(Subtract l/r.)
= 102 + 28
(Add l/r.)
= 130
(Add.)
Which of the following represents
112 + 18 - 33 · 5 in simplified form?
1.
2.
3.
4.
-3,236
4
107
16,996
Answer Now
Simplify
16 - 2(10 - 3)
1.
2.
3.
4.
2
-7
12
98
Answer Now
Simplify
24 – 6 · 4 ÷ 2
1.
2.
3.
4.
72
36
12
0
Answer Now