2.1 comparing & ordering fractions

To compare fractions you
can draw a picture or use
the “Butterfly” method.

4
3
6
5
<
Draw a picture Use >, <, or =.

Use >, <, or =.
5
3
3
2
9 10<
<
“Butterfly” method

Use >, <, or =.
10
3
4
1
12 10>
>
“Butterfly” method

To order fractions you
can draw a picture or
use the Least Common
Denominator (LCD).

4
3
6
5
Draw a picture
Order :
least to greatest
2
1

4
3
2
1
6
5
Order the fractions from
least to greatest.
, ,

One way to compare or
order fractions is to
express them with the
same denominator.

Any common denominator
could be used. But the
Least Common
Denominator (LCD)
makes the computation
easier.

The Least Common
Denominator is the
Least Common Multiple
of the denominators.
LCD = LCM

Use LCD
List the fractions in order
from greatest to least.
3
2
,
9
5
,
12
7
,
6
1

Use LCD
Step 1: Find the
LCM of the
denominators
3
2
,
9
5
,
12
7
,
6
1

6, 12, 18, 24, 30, 36, 42, 48…
LCD = 36
Find the
LCD:
12, 24, 36, 48 …
9, 18, 27, 36, 45 …
3, 6, 9, 12, 15, 18, 21, 24,
27, 30, 33, 36 …

Step 2: Write
equivalent
fractions.
=
6
1
36x 6
x 6
6
=
12
7
36x 3
x 3 21
=
9
5
36x 4
x 4
20 =
3
2
36x 12
x 1224

G L
Step 3:
Compare the
numerators
=
6
1
36
6
=
12
7
36
21
=
9
5
36
20 =
3
2
36
24

Use LCD
In order from
greatest to least:
6
1
,
9
5
,
12
7
,
3
2

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