Fractions/Finding Common Denominators

Common Denominators

100

Find a common denominator for the pair of fractions:

2/5 and 1/6

30, 60, 90 ...

200

Find a common denominator for the pair of fractions:

1/3 and 4/5

15, 30, 45 ...

300

Find a common denominator for the pair of fractions:

3/10 and 9/8

40, 80, 120 ...

400

Find a common denominator for the pair of fractions:

7/9 and 2/3

9, 18, 27 ...

500

Find a common denominator for the pair of fractions:

5/6 and 8/21

42, 84, 126 ...

Adding fractions

100

1/2 + 2/5 =

9/10

200

1/3 + 1/6 =

3/6 = 1/2

300

5/9 + 1/4 =

29/36

400

7/25 + 9/20 = 

83/100

500

1/10 + 4/7 =

47/70

Subtracting fractions

100

1/2 - 1/3

1/6

200

8/10 - 1/2

3/10

300

3/4 - 1/12

8/12 = 2/3

400

7/8 - 1/3

13/24

500

5/6 - 1/4

7/12