Transcript Document

1-4: Order of Operations
http://studyjams.scholastic.com/studyjams/jams/math/algebra/aorder-of-operations.htm
G
E
M
D
S
A
LEFT
TO
RIGHT
P: ( ) [ ]
E: exponents
M: x
D:
A: +
S:
k
Order of Operations
Where do I start?
You evaluate an expression by finding its
value..."working the problem"
Jack and Jill were asked to
evaluate the expression 3 + 4 x
14
2 and got different answers!
11
Jack explained how he
got his answer....
3+4x2=
7 x 2 = 14
Jill explained how she
got her answer....
3+4x2=
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
perilous poles
Please
Evaded enraged
elephants
Excuse
Manipulated and dodged multipleAmbled swiftly around snakes
trees and divides as they
and army ants
appeared
My
Dear
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!
23 + (6-3) x 4 ÷ 2+8=
23 +
3
x 4 ÷ 2+8=
2x2x2
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.
8 +
3 x 4 ÷ 2+8=
3
Click here!
23 + (6-3) x 4 ÷ 2+8=
Then, divide or multiply from left to
right. Solve one problem before
answering the next!
23 +
3
x 4 ÷ 2+8=
8 +
3
x 4 ÷ 2+8=
8 +
8 +
12
6 +8=
÷ 2+8=
23 + (6-3) x 4 ÷ 2+8=
Finally, subtract and add any
remaining facts as they appear
from left to right.
23 +
3
x 4 ÷ 2+8=
8 +
3
x 4 ÷ 2+8=
8 +
12
8 +
6 +8=
8 +
÷ 2+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
So, who was right?
11
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
10 -3 x 2
multiply or
divide
4 x 32
multiply or
divide
(8 -5) x 23
add or
subtract
evaluate inside
parentheses
evaluate inside
parentheses
add or
subtract
value
4
36
multiply or
divide
multiply or
divide
24
evaluate
powers
Solve these expressions using the
rules we just learned. How did order
affect the results?
144 - (7 x 12) =
(144 - 7) x 12 =
144 - 84 =
60
137 x 12 =
1644
Pull
Pull
Pull
7 + 144 x 12 =
(7 x 12) + 144 =
84 + 144 =
228
Pull
Pull
Please
7 + 1728 =
1735
Pull
Excuse
My
Aunt
Dear
Sally
3
Practice Questions
1. 32 + 4
3. (3x5) + (6/2) 18
4. 22 + 5 x 2 14
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
13
Ch 1-4
Grade: «grade»
Subject: «subject»
Date: «date»
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