Transcript Comparing and Ordering Fractions

Comparing and Ordering
Fractions
Strategy
• Make sure the denominators are the same.
• Compare the numerators.
•If the denominators are not the same, then rewrite the
fractions using a common denominator.
•The new fractions should be equivalent to the original
fractions.
Writing Equivalent Fractions
• One way to find a common denominator is
to multiply the two original denominators.
5
6
>
3
4
6 x 4 = 24
20 > 18
x4
20
24
18
24
x6
•Another way to compare fractions is to find the LCM of both
denominators.
•Use the LCM as the new denominator in the equivalent
fractions.
9, 18, 27, 36, 45
5
9
7
<
12
12, 24, 36, 48, 60
20 < 21
x4
20
36
21
36
x3
Ordering Fractions
• Find the LCM of the denominators.
• Use the LCM to write equivalent fractions.
• Put the fractions in order using the
numerators.
Example - Order from Least to
2
1
Greatest: 3
5
8
x5
4
x8
15
40
16
40
10
40
x 10
8, 16, 24, 32, 40, 48
5, 10, 15, 20, 25, 30, 35, 40
4, 8, 12, 16, 20, 24, 28, 32, 36, 40
1/4 < 3/8 < 2/5
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