Rename Before You Subtract

Mrs. YoungEMC 1

Subtract the fractions

6 - 1 47

Step 1:

• Rename 6. Use 7 for the denominator because the denominator in the problem is 7

6=

5+

77

6=

5+

1

6=

5 77

Step 1 continued…

• Our new subtraction problem is:

6-

1 47

=

= 1 4

7

5 77

Step 2:

• Subtract the fractions

1 47

5 77-

37

Step 3:

• Subtract the whole numbers.

1 47

5 77-

374

Step 4:

• Simplify the fraction to lowest terms, if possible.

• In this case, the answer is in lowest terms.

374

Subtract the fractions

5 - 1 56

16

Step 1:• Rename Use 6 for the

denominator5

16

=

4+

16

5=

5

=

4 66

16+

1 +

+

16

+

=

4 76

Step 1 continued

• Our new subtraction problem is:

5-

2 56

=

= 2 5

6

4 76

16

Step 2:

• Subtract the fractions

2 56

4 76-

26

Step 3:

• Subtract the whole numbers

2 56

4 76-

262

Step 4:

• Simplify the fraction to lowest terms, if possible.

262

In order to simplify the fraction, you must find the GCF of the numerator and the denominator.

Remember to list all of the factors:

2: 1, 2

6: 1, 2, 2, 6

GCF = 2

=÷

÷

22

13

2

Subtract the fractions

6 - 2 23

15

First things first!

• When we have unlike fractions we have to start by making like fractions (make equivalent fractions)!

6 - 2 23

15

15

- x 3

x 3

23

x 5

x 5= 3

15-

1015

Our new problem is:

6 - 21015

315

Step 1:• Rename using 15 as

the denominator6

315

=

5+

315

6 =

6

=

5 1515

315+

1 +

+

315

+

=

5 1815

315

Step 1 continued…

• Our new problem is:

6-

2 1015

=

= 2 10

15

5 181515

3

Step 2:

• Subtract the fractions

2 1015

5 1815-

815

Step 3:

• Subtract the whole numbers

2 1015

5 1815-

8153

Step 4:

• Simplify the fraction to lowest terms, if possible.

• In this case the fraction is in lowest terms.

8153

Subtract the fractions

4 - 2 23

16

First things first!

• When we have unlike fractions we have to start by making like fractions (make equivalent fractions)!

4 - 2 23

16

16

- x 1

x 1

23

x 2

x 2= 1

6-

46

Our new problem is:

4 - 2 46

16

Step 1:• Rename using 6 as the

denominator4

16

=

3+

16

4 =

4

=

3 66

16+

1 +

+

16

+

=

3 76

16

Step 1 continued…

• Our new problem is:

4-

2 23

=

= 2 4

6

3 766

1

Step 2:

• Subtract the fractions

2 46

3 76-

36

Step 3:

• Subtract the whole numbers

2 46

3 76-

361

Step 4:

• Simplify the fraction to lowest terms, if possible.

361 =÷

÷

33

12

1

In order to simplify the fraction, you must find the GCF of the numerator and the denominator.

Remember to list all of the factors:

1: 1, 3

6: 1, 2, 2, 6

GCF = 3

Your turn!

• Subtract

8 - 2 56

26

Try another!

• Subtract

4 - 3 15

18