Least Common Denominator
Adding Fractions with Unlike Denominators
Subtracting Fractions with Unlike Denominators
Understanding Fractions
100

1/2 and 3/5

10

100

1/4 + 2/3 = 

11/12

100

4/5 - 1/3 =

7/15

100

What is a denominator?

The number underneath the line in a fraction

200

5/12 and 2/9

36

200

4/9 + 1/6 =

22/36

200

4/3 - 2/7 =

22/21 

200

What is a numerator?

The number above the line in a fraction

300

1/7 and 4/8

56

300

3/4 + 1/9 =

31/36

300

3/4 - 1/9 =

23/36

300

What does equivalent mean?

Equal in value or same amount

400

9/10 and 5/6

30

400

1/2 + 1/3 =

5/6

400

6/7 - 1/2 =

5/14

400

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

Find a common denominator 

500

1/4 and 2/3

12

500

1/4 + 3/7 =

19/28

500

9/10 - 1/4 =

13/20

500

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

Write equivalent fractions with your new denominator