Adding and Subtracting Fractions

Lowest Common Multiple

100

Lowest common multiple between 2 and 4

4

200

Lowest common multiple between 3 and 4

12

300

Lowest common multiple between 5 and 25

25

400

Lowest common multiple between 9 and 4

36

500

Lowest common multiple between 4 and 10

20

Adding Fractions

100

3/8 + 3/8

6/8 = 3/4

200

2/3 + 1/6

5/6

300

2/5 + 1/2

9/10

400

5/6 + 1/4

13/12 = 1 1/12

500

3/4 + 7/8

26/16 = 1 10/16 = 1 5/8

Subtracting Fractions

100

7/8 - 5/8

2/8 = 1/4

200

7/10 - 1/2

2/10 = 1/5

300

2/3 - 1/12

7/12

400

4/6 - 1/4

5/12

500

5/6 - 3/9

9/18 = 1/2

Mixed Numbers

100

2 1/3 + 3 1/3

5 2/3

200

3 2/5 - 2 1/5

1 1/5

300

3 2/3 - 1 1/6

2 3/6

400

4 2/4 + 1 1/3

5 10/12

500

3 3/5 + 2 3/4

6 7/20

Miscellaneous

100

Lowest common multiple between 2 and 4

4

200

Are these fractions equivalent? 5/8 and 30/48

If so, what did we multiply by?

yes, multiply by 6/6

300

Are these fractions equivalent: 3/5 and 8/10

If so, what did we multiply by?

no, 3/5 = 6/10 (should multiply by 2/2)

400

Write the mixed number as an improper fraction: 3 3/4

15/4

500

What is the lowest common denominator for adding: 3/6 + 2/9? What is the answer?

LCD = 18

9/18 + 4/18 = 13/18