Transcript Fractions and Decimals

Lesson 5
Ordering and Comparing Fractions
1.
What do the symbols < and > mean?
2.
7
4
and
Find the LCD for
.
10
7
3.
3 1
1
Find the LCD for , and .
4 3
6
Target:
Compare fractions with like and unlike denominators
to find the smallest or largest fraction.
1.
Find the least common denominator (LCD) for the
fractions in the set.
2.
Change each fraction to an equivalent fraction using
the LCD.
3.
Compare the numerators.
In a recent survey, three-fifths of people liked peanut
butter and jam. One-third liked grilled cheese
sandwiches. Compare three-fifths and one-third to find
which food was most popular.
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3 1
,
5 3
The denominators are 3 and 5.
3: 3, 6, 9, 12, 15, …
5: 5, 10, 15, 20, 25, …
The LCM = 15, so the LCD = 15.
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Make equivalent fractions with denominators of 15.

Compare the numerators. Nine is larger than 5.
9 5
3 1
 then  .
If
15 15
5 3
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The group that liked peanut butter and jam sandwiches
was larger.
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1 1 1
List the following fractions from least to greatest: , ,
2 6 3
The denominators are 2, 6 and 3.
2: 2, 4, 6, 8, 10
6: 6, 12, 18, 24
3: 3, 6, 9, 12, 15
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The LCM = 6, so the LCD = 6.
Make equivalent fractions.
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Compare numerators.
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Substitute the original fractions and order.
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1 3
1 2
 and 
2 6
3 6
1 2 3
 
6 6 6
1 1 1
, ,
6 3 2
Find a fraction between 1 and 1 . Write in simplest form.
6
2
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The denominators are 6 and 2.
6: 6, 12, 18, …
2: 2, 4, 6, 8, …

Make equivalent fractions.
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Compare the fractions. 1  3
6 6
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A fraction that would be between 1 and 1 is 2  1 .
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6
2
6
3
1.
Compare each pair of fractions. Replace the
with <, > or = to make a true sentence.
5
7
??
6
9
2.
3
11
??
4
14
Write the fractions in order from least to greatest.
3 7 6
, ,
5 10 15
What is the process for ordering three fractions with three
different denominators?