The document discusses comparing and ordering fractions. It begins by defining the least common denominator (LCD) as the least common multiple of the denominators of two fractions. Examples are then provided of finding the LCD to compare fractions and determining which fraction is larger. The document concludes by explaining how to order three fractions by first finding the LCD and then writing the fractions with equivalent denominators before comparing their numerators.

1. Mr. Williams
5.5 Ordering Fractions GESD
jwilliams@gesd40.org
http://mrwilliams.edublogs.org
Image: 'Fractional Hugs and Kisses'
www.flickr.com/photos/84617037@N00/60431147
Objective: Compare and order fractions.
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2. Vocabulary
Least Common Denominator (LCD) ­ the least common multiple of the
denominators of two fractions.
Image: 'Chairs'
www.flickr.com/photos/46555636@N00/2981776
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3. Which is larger?
3 7
Compare and . Which is larger?
4 8
http://www.shodor.org/interactivate/activities/FractionSorter/
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4. Comparing Fractions using the LCD.
5 7
Compare and .
6 9
1. Find the LCD: The LCD of 6 and 9 is 18.
5 5 x 3 15 7 7 x 2 14
= 18
6
=
6 x 3 = 18 9 = 9 x 2
Which is bigger? 15 14
or
18 18
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5. 5 2 1 1 >
9 9 6 8 >
=
5 3 2 6 <
7 4 5 15
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6. Ordering Fractions
3 2 1
Order the fractions , , from least to greatest.4
10 5
1. What is the LCD of 10, 5, and 4?
Your right, it's 20!
2. Make equivalent fractions using 20 as the denominator.
3 x 2 6
=
10 x 2 20
2 x 4 8 =
5 x 4 20
1 x 5 5 =
4 x 5 20
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7. Order the following fractions from least to greatest in your math notes!
3 2 5 5 3 7
4 3 8 9 4 12
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8. 8