Transcript Integers - Greenebox

Integers
Concepts and definitions
for Signed Numbers
Copyright 2012 by Lynda Aguirre
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Definitions
N: Natural (counting) Numbers {1, 2, 3, 4,…}
you naturally start to count objects with 1, 2,…
W: Whole Numbers {0, 1, 2, 3, 4,…}
Add a “hole” (a zero) to the natural numbers
Z: Integers {…, -3, -2, -1, 0, 1, 2, 3, 4,…}
Integers are the first extension to the set of whole numbers
Copyright 2012 by Lynda Aguirre
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Representations of Integers
Temperature
Number Line
Color Coding
Copyright 2012 by Lynda Aguirre
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Absolute Value
Definition: The distance from zero to any integer
Symbol:
This is asking the question: How far is it from zero to negative five on a number line?
5 spaces
Copyright 2012 by Lynda Aguirre
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Practice Problems
12
7
Copyright 2012 by Lynda Aguirre
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Integers in Word Problems
The temperature in Fargo, ND is -12 degrees. On the same day, the temperature
In Anchorage, AK is -52. How much colder is it in Anchorage?
Copyright 2012 by Lynda Aguirre
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Sue had $15 in her checking account. If she wrote a check for $25, and the
Bank charged her $20 for being overdrawn, what is her current account balance?
Add the two negative numbers first
Copyright 2012 by Lynda Aguirre
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Sammy owns a hotdog stand. If he sold 45 hot dogs at lunch time
at $3 each, how much money did he make?
Sammy sells a total of 427 hot dogs this week. If he pays a cart rental fee
of $500 a week, how much money does he have at the end of the week?
Copyright 2012 by Lynda Aguirre
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Sign Rules
Sign Rules for
Integers
Addition &
Subtraction
Multiplication and
Division
Same Sign:
++ or - -
*Add the numbers
Two negatives
make a positive
Different Signs:
+ - or - +
Big – Small
Keep the sign of the
bigger number
Keep the sign of the
bigger number
Copyright 2012 by Lynda Aguirre
One negative stays
negative
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Practice Problems
Copyright 2012 by Lynda Aguirre
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