Fractions - NSW Department of Education

Fractions common fractions / addition Common fractions are represented by one number over a dividing line. The bottom number is called the DENOMINATOR.

The top number is called the NUMERATOR.

3 4

It tells us the size of the part that the whole is divided into.

It tells us how many of the divided parts.

Adding fractions with the same denominator

1 + 1 = 4 4

1 4

2 + 3 = 8 8

= 2 = 1 4 2

1 4

2 8

= 5 8

3 8

Using an empty number line 4 + 2 = 8 8

0

1 8

1 25

0

1 5

2 8

+ 2 8

3 8

4 8

5 8

6 8

7 8

1

+ 4 =

1

+1

5

3 5

4 5

1

1

1 5

1

2 5

1

+1

5

2 5

1 8

+1

5

1

3 5

1

2 8

3 8

etc

+1

5

4 5

1

5

2

2

1 5

For more homework help, tips and info sheets go to www.schoolatoz.com.au © Owned by State of NSW through the Department of Education and Communities 2011. This work may be freely reproduced and distributed for non-commercial educational purposes only. Permission must be received from the department for all other uses.

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Adding fractions with different denominators Equivalent fractions are fractions that are equal in value but have different names as the whole is broken up into different parts. A knowledge of equivalent fractions is helpful.

1 =

2 = 4

2

4 = 50 8 100

Using arrays

1 + 3 = 4 8

2 8

1 4

4 + 4 = 5 10

2 8

=

4 10

4 5

= 5 8

3 8

8 10

=

8 10

=

2 1 10 (or 1 15 )

or 4 + 4 = 10 5

( 104 )

2 + 4 = 6 = 5 5 5

1 15

Using an empty number line

5 + 1 1 ( 2 2 8

= 4 8

) = 58 + 48 = 98 = +1

+1

8

0

1 8

2 8

3 8

4 8

5 8

+1

8

6 8

+1

8

7 8

1 18 8

1

1

1 8

1

2 8

1

3 8

etc

For more homework help, tips and info sheets go to www.schoolatoz.com.au © Owned by State of NSW through the Department of Education and Communities 2011. This work may be freely reproduced and distributed for non-commercial educational purposes only. Permission must be received from the department for all other uses.

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