Transcript Order of Operations

0011 0010 1010 1101 0001 0100 1011
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TEKS 6.2E
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Lesson 6 (2nd 6 Weeks)
0011 0010 1010 1101 0001 0100 1011
• The order in which
operations are computed
in an expression.
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0011 0010 1010 1101 0001 0100 1011
• Follow this order of operations:
 STEP 1:
Simplify any operations in
parentheses and brackets. If there is
more than one operation within a set
of parentheses, follow the order of
operations in steps 2, and 3.
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• STEP 2: Calculate all
multiplication and division
from left to right.
0011 0010 1010 1101 0001 0100 1011
• STEP 3: Calculate all
addition and subtraction
from left to right.
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•
A phrase that is helpful in
0011 0010
1010 1101 0001 0100 1011
remembering
the order of
operations is: “Please Excuse
My Dear Aunt Sally”
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Please (Parentheses, first)
Excuse (Exponents-we don’t
do)
0011 0010 1010 1101 0001 0100 1011
My Dear (Multiply and Divide
from Left to Right)
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Aunt Sally (Add and Subtract
from Left to Right)
0011 0010 1010 1101 0001 0100 1011
• Remember: Multiplication is not always
done before division. Work left to right.
Whichever one comes first, is done first.
Same for addition and subtraction.
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0011 0010 1010 1101 0001 0100 1011
Performing operations left to
right only
21  6  3 5
21  6  3  5
27  3 5
27  3 5
9 5
 45
The rules for
order of
operations exist
so that everyone
can perform the
same consistent
operations and
achieve the same
results. Method 2
is the correct
method.
Performing operations using
order of operations
21  6  3 5
21  6  3  5
21  2  5
21  2  5
21 10
 31
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Can you imagine
what it would be like
if calculations were
performed differently
by various financial
institutions or what if
doctors prescribed
different doses of
medicine using the
same formulas and
achieving different
results?
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Simplify the Expression
12÷3+4·6-2·3
0011 0010 1010 1101 0001 0100 1011
• 1. There are no parentheses
• 2. Multiply and divide from left to right.
12÷3+4·6-2·3
4 + 24 - 6
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3. Add and subtract from left to right.
4+24-6
28-6
22
4. The expression simplifies to 22.
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1. (8+3)-5
11-5
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A good rule of
thumb is to
underline the
part of the
expression that
you are doing
first.
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2. 24 - (19 - 19)
24 – 0
24
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3. 5 x 8 - 3 x 4
40 -12
28
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4.
3+5·4
3 + 20
23
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5. (24 - 10) - 3 · 3
14 – 3 · 3
14- 9
5
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6. 4(22-18÷3) · 5
4(22- 6 )· 5
4·16 · 5
64·5
320
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7. 3(18 - 12) - (5 - 3)
3 x 6- 2
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18- 2
16
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If a = 5 and b = 4, solve
5a – 3b
5 x 5a – 3 x 4b
25 - 12
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A family of five is going
to the zoo. Adult tickets
are $7 each and children’s
tickets are $5 each.
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Write an equation to
find c, the total cost of
going to the zoo if you
buy two adult and three
children’s tickets.
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Solve the equation you
wrote.
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(2 x 7) + (3 x 5) = c
0011 0010 1010 1101 0001 0100 1011
(2 x 7) + (3 x 5) = c
14 +15 = c
$ 29 = c
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