Steps
What is the first step when adding or subtracting fractions with unlike denominators?
Find the common denominator (LCM)
2 1
____ + ____ =
3 4
11
___
12
1 1
____ - ___ =
3 4
1
___
12
3 2
2 ____ + ___ =
4 3
5
3 ____
12
What is a denominator?
The number underneath the line in a fraction
What is the second step when adding or subtracting fractions with unlike denominators?
Write equivalent fractions with your new denominator
3 2
____ + ___ =
4 3
5
1 ____
12
2 1
____ - ___ =
3 5
7
____
15
1 1
4 ____ + ___ =
3 2
5
4 ____
6
What is a numerator?
The number above the line in a fraction
What is the third step when adding or subtracting fractions with unlike denomiantors?
Add or subtract the numerator (keep the denominator)
4 3
____ + ___ =
5 4
11
1 ____
20
1 1
____ - ___ =
2 5
3
____
10
3 2
____ + 3 ___ =
5 5
4
What does equivalent mean?
Equal in value or same amount
What is the fourth step when adding or subtracting fraction with unlike denomiantors?
Simplify the fraction if needed
6 5
____ + ___ =
7 6
29
1 ____
42
4 2
____ - ___ =
5 3
2
____
15
1 4
3 ____ - ___ =
5 6
8
2 ____
15
What does simplify mean?
To reduce a fraction to it's simplest form
What is the fifth step when adding or subtracting fractions with unlike denominators?
If improper, change to a mixed number fraction
5 7
____ + ___ =
7 8
33
1 ____
56
5 1
____ - ___ =
7 3
8
____
21
2 2
4 ____ - 3 ___ =
6 3
2
____
3
What is a common denominator?
two or more fractions have the same denominator