Name ——————————————————————————
LESSON
1.3
GOAL
Date ——————————————
CA Standard
NS 2.4
Reteach
For use with pages 18–22
Use factors to write equivalent fractions.
VOCABULARY
Fractions that represent the same part-to-whole relationship are
called equivalent fractions.
A fraction is in simplest form if its numerator and denominator
have 1 as their greatest common factor.
EX AM PLE
1 Writing Fractions
At a pet store, there are 12 kittens. Four of the kittens are gray.
What fraction of the kittens at the pet store are gray?
Solution
Lesson 1.3
The kittens in the pet store are arranged in the diagram.
Using the diagram, you can write two equivalent fractions.
Number of gray kittens
4
12
Number of kittens
Number of groups of 2 gray kittens
2
6
Number of groups of 2 kittens
Copyright © Houghton Mifflin Company.
4
The fractions }
and }2 are equivalent fractions because
12
6
they represent the same part-to-whole relationship.
Exercise
for Example 1
..................................................................................................
1. What fraction of the kittens in Example 1 are white?
Write two equivalent fractions.
EX AM PLE
2 Writing Equivalent Fractions
Write two fractions that are equivalent to }6 .
9
Multiply or divide the numerator and denominator
by the same nonzero number to find an equivalent fraction.
6
62
12
9
92
18
Multiply numerator and denominator by 2.
6
63
2
9
93
3
Divide numerator and denominator by 3,
a common factor of 6 and 9.
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Name ——————————————————————————
LESSON
Reteach
1.3
Date ——————————————
continued
For use with pages 18–21
Exercises
for Example 2
...................................................................................................
Write two fractions that are equivalent to the given fraction.
6
2. }
10
E X A M P LE
12
3. }
16
4
4. }
5
3 Simplifying Fractions
Write the fraction in simplest form.
9
b. }
16
12
a. }
14
Solution
Lesson 1.3
1
62
12
a. } }
14
72
1
}6
7
The GCF is 2.
9
b. }
16
The GCF is 1.
The fraction is in simplest form.
Exercises
for Example 3
...................................................................................................
Write the fraction in simplest form.
15
5. }
18
20
7. }
25
4 Using Fractions in Simplest Form
You are helping with the laundry. Eight out of 10 socks are red. Write
the number of red socks as a fraction in simplest form of the total
number of socks. Then write the number of non-red socks as a
fraction in simplest form of the total number of socks. Are the
fractions equivalent?
Red Socks
Other Socks
8
5
Non-red socks
Red socks
2
1
}} } }
10
4
10
Total socks
Total socks
5
4
1
Answer: No, } and } are not equivalent fractions.
5
5
}}}
Copyright © Houghton Mifflin Company.
E X A M P LE
8
6. }
17
Exercise
for Example 4
..................................................................................................
8. In your math class, 12 students participate in after-school clubs.
There are 21 students in your math class. Write the number of
students who participate in after-school clubs as a fraction of the
total number of students. Then write the number of students who
do not participate in after-school clubs as a fraction of the total
number of students. Write each fraction in simplest form.
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