Adding and Subtracting Fractions w/ Unlike Denominators

Fractions as Division

100

Write 4 divided by 7 as a fraction. 

4/7

200

Write 3/5 as a division problem. 

3 ÷ 5

300

What is the first step when adding or subtracting fractions with unlike denominators?

Find the common denominator. 

400

Write 18 divided by 4 as a fraction. 

4  1/2

500

Write 22 divided by 6 as a fraction. 

3  2/3 

Adding Fractions w/ unlike denominators

100

5/8 + 1/2 

1 1/8 

200

1/4 + 2/3 

11/12 

300

1/2 + 6/7

1  5/14

400

1/4 + 2/9

17/36

500

3/8 + 2/3 

1  1/24

Subtracting fractions w/ unlike denominators

100

7/12 - 1/2 

1/12

200

7/9 - 1/6

11/18

300

4/5 - 1/3

 7/15

400

1 - 5/6 - 1/12 

1/12

500

2/3 - 2/8

5/12 

Adding and subtracting mixed numbers w/ unlike denominators

100

 3 5/8 + 2 1/4

5  7/8 

200

7 5/6 - 2 1/4

5  7/12

300

12 1/9 + 9 5/6 

 21  17/18

400

 7 8/9 + 9 5/12 

17 11/36 

500

  6 3/8 - 3 5/6 

2  13/24