Equivalent Fractions

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Transcript Equivalent Fractions

EQUIVALENT
FRACTIONS
Mrs. Walker
4 th Grade
VOCABULARY: EQUIVALENT FRACTIONS
Equivalent fractions are fractions that name the same amount.
2
4
=
4
8
CREATING EQUIVALENT FRACTIONS
Multiply the numerator and denominator by the
same number.
We can choose any number to multiply by. Let’s multiply by 2.
3 x2
6
=
10
5 x2
So, 3/5 is equivalent to
6/10.
CREATING EQUIVALENT FRACTIONS
Divide the numerator and denominator by a
common factor. (It has to be a common factor
to work with division.)
To divide we MUST use a common factor. What number is a common factor of 6 ?
10
6 ÷2
3
=
5
10 ÷ 2
So, 3/5 is equivalent to
6/10.
For larger numbers, make equivalent fractions using
division. Remember, divide by a common factor.
28 ÷ 7
4
=
35 ÷ 7
5
In this example, we can divide both numbers by 7.
28/35 is equivalent to 4/5.
Think to yourself…
What number can I
divide into both 28
and 35?
VOCABULARY: SIMPLEST FORM
Fractions are in simplest form when the
numerator and denominator do not have
any common factors besides 1.
Examples of fractions that are in simplest form:
4
5
2
11
3
8
VOCABULARY: SIMPLIFY
Simplify means to reduce a fraction to it’s
simplest form.
WRITING FRACTIONS IN SIMPLEST FORM.
1. Find the greatest common
factor (GCF) of the numerator
and denominator.
2. Divide both numbers by the
GCF.
EXAMPLE:
20 ÷ 4 5
=
28 ÷ 4 7
20
28
1 x 20
1 x 28
20: 1, 2, 4, 5, 10, 20
28: 1, 2, 4, 7, 14, 28
Common Factors: 1, 2, 4
2 x 10
4x5
2 x 14
4x7
Simplest
Form
GCF: 4
We will
divide by 4.
HOMEWORK TIME