Estimate to Add or Subtract
Use the least common denominator to write an equivalent fraction for each fraction
Add fractions
Subtract Fractions
Word Problems
100

8/9 + 4/7

1 1/2 

100

2/5 , 1/10

4/10, 1/10

100

2/7 + 2/5

24/35

100

3/4 - 3/10

9/20

100

Jennifer had a 7/8 foot board. She cut off a 1/4 foot piece that was for a project. In feet, how much of the board was left?

5/8 foot 

200

5/6 - 3/8

1/2

200

5/6 , 3/8 

20/24 , 9/24

200

7/8 + 1/3

1 5/24

200

11/18 - 1/6 

4/9

200

Mike is mixing paint for his walls. He mixes 1/6 gallon blue paint and 5/9 gallon green paint in a large container. What fraction represents the total amount of paint Mike mixes?

19/24

300

3 2/5 - 5/8 

3

300

1/3 , 2/7 

7/21 , 6/21 

300

1/5 + 3/4

19/20

300

5/7 - 1/4 

13/28

300

On Fride, 1/6 of band practice was spent on trying on uniforms. The band spent 1/4 of practice on marching. The remaining practice time was spent playing music. What fraction of practice time was spent playing music?

7/12

400

1 5/6 + 2 2/11

4

400

7/12 , 5/18

21/36 , 10/36

400

8/9 + 5/6 

1 13/18 

400

11/12 - 7/15

9/20

400

Tom has 7/8 cup of olive oil. He uses 1/2 cup to make a salad dressing and 1/4 cup to make tomato sauce. How much olive oil does Tom have left? 

1/8 cup 

500

11/12 + 6/10

1 1/2 

500

5/14 , 8/42

15/42 , 8/42

500

1/2 + 2/5 + 3/4= 

1 13/20

500

4/9 - 1/6

5/18

500

Keisha makes a large sandwich for a family picnic. She takes 1/2 of the sandwich to the picnic. At the picnic her family eats 3/8 of the whole sandwich. What fraction of the whole sandwich does Keisha bring back from the picnic?

1/8