1. Least Common Denominator
Least Common Multiple
Least Common Denominator
Giant One
Comparing Fractions
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2. Name the first six multiples of 6
Least Common Multiple
The product of a whole number multiplied by any other whole number is called a multiple.
Name the first six multiples of 6
6, 12, 18, 24, 30, 36

3. Name the first six multiples of 5
Least Common Multiple
Name the first six multiples of 5
5, 10, 15, 20, 25, 30

4. Least Common Multiple
A Common Multiple is a number
that is a multiple of two numbers.
Here are common multiples for the
numbers 4 and 10
4 = 4, 8, 12, 16, 20, 24
10 = 10, 20, 30, 40, 50,

5. Least Common Multiple
is the smallest
number that a set of given numbers divides
evenly into.
LCM -
Least Common Multiple
LCM is also known as finding the Least
Common Denominator
It is useful to know how to do this so you can find a common denominator when adding or subtracting fractions.

6. Least Common Multiple
To find the LCM 4 and 12
1) List the multiples of both numbers
4 = 4, 8, 12, 16, 20…
LCM is 12
12 = 12, 24, 36, 48…
2) Find the least multiple that both numbers have in common.
This method is useful if both numbers are small.

7. Least Common Multiple
What is the LCM of 6 & 8?
6 = 6, 12, 18, 24, 30, 36
8 = 8, 16, 24, 32, 40, 48

8. Least Common Multiple
What is the LCM of 3 & 9?
3 = 3, 6, 9, 12, 15, 21,
9 = 9, 18, 27, 36, 45, 54

9. LCM = 60 Make a List of Multiples 10 = 10, 20, 30, 40, 50, 60, 70, 80…
Least Common Multiple
Find the LCM of 10 and 12.
Make a List of Multiples
10 = 10, 20, 30, 40, 50, 60, 70, 80…
12 = 12, 24, 36, 48, 60, 72…
LCM = 60

10. LCM = 150 Make a List of Multiples
Least Common Multiple
Find the LCM of 25 and 30.
Make a List of Multiples
25 = 25, 50, 75, 100, 125, 150, 175…
30 = 30, 60, 90, 120, 150, 180…
LCM = 150

11. Least Common Multiple
What is the LCM used for?
The LCM is used to find common denominators so that fractions may be easily compared, added, or subtracted.
GIANT ONE
GIANT ONE
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Giant One
The Giant One is used to find equivalent fractions.
It is used to reduce or simplify fractions.
The giant one works because of the Identity Property.
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Giant One
Identity Property states that any number multiplied by one equals itself
This is useful to know so you can find a common denominator for adding and subtracting fractions.
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14. > < = Large # Small # Means larger or greater than
Comparing Fractions
To compare fractions sometimes we use
inequality symbols rather than an equal sign.
>
Means larger or greater than
<
Means smaller or less than =
Means equal to
Large #
Small #
The hungry alligator eats the larger number.

15. 5 4 5 is greater than 4 > < = Means larger or greater than
Comparing Fractions
To compare fractions sometimes we use
inequality symbols rather than an equal sign.
>
Means larger or greater than
<
Means smaller or less than =
Means equal to 5 4
5 is greater than 4

16. 5 4 4 > < = If this method confuses you…try this!
Comparing Fractions
To compare fractions sometimes we use
inequality symbols rather than an equal sign.
>
Means larger or greater than
<
Means smaller or less than =
Means equal to 5 4 4
If this method confuses you…try this!

17. < > 5 4 ess than If this method confuses you…try this!
Comparing Fractions
<
ess than
reater than
>
Left hand = Less than 5 4
If this method confuses you…try this!

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Comparing Fractions
Which is greater?
>
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Comparing Fractions
Use < or > to compare the fractions below.
>
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20. copyright©amberpasillas2010
Comparing Fractions
Use < or > to compare the fractions below.
>
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21. copyright©amberpasillas2010
Comparing Fractions
Use < or > to compare the fractions below.
<
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22. copyright©amberpasillas2010
Comparing Fractions
The GCF and LCM are used so regularly that
most people find them mentally.
GCF = 1
GCF = 5 1) 2)
LCM = 72
LCM = 60
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23. copyright©amberpasillas2010
Comparing Fractions
The GCF and LCM are used so regularly that
most people find them mentally.
GCF = 4
GCF = 4 1) 2)
LCM = 60
LCM = 24
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Comparing Fractions
THE END!
Take out your
study guide.
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25. Least Common Denominator#6
Least Common Denominator
TO FIND THE LCM OF 4 and 12:
1) List the multiples of both numbers
4 = 4, 8, 12, 16, 20…
12 = 12, 24, 36…
2) Find the least multiple that both numbers have in common.
LCM is 12
Least Common Multiple is also known as LCD.

26. Comparing Fractions > #7 < >
Read these symbols from left to right.
<
Less than
>
Greater than
Less than or equal to
Greater than or equal to
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To compare fractions you must show your work!
>