Adding and Subtracting Fractions with Unlike Denominators Worksheet

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NEO
Adding and Subtracting Fractions with Unlike Denominators worksheet. If the denominators are not the same, then you have to use equivalent fractions which do have a common denominator. To do this, you need to find the least common multiple (LCM) of the two denominators. To add fractions with unlike denominators, rename the fractions with a common denominator.
1. Basic Arithmetic Skill
Adding or Subtracting Fractions with Different Denominators
Evaluate each expression.
3 2 9
1) + 2) 1 +
4 5 5
13 3 5 1
3) + 4) −
7 2 8 7
3 1 3
5) 1 + 6) +
7 7 2
4 9 5 1
7) + 8) +
5 7 4 2
7 5 1
9) + 10) 7 −
4 8 4
3 4 3
11) + 12) 3 −
2 3 7
2 10 1 1
13) + 14) +
3 7 3 2
13 4 1
15) 4 − 16) +
7 5 3
3 11 4 3
17) + 18) +
2 6 7 2
5 1 3 13
19) + 20) +
7 4 2 7
2. Answers to Adding or Subtracting Fractions with Different Denominators
23 14 47 27
1) 2) 3) 4)
20 5 14 56
10 23 73 7
5) 6) 7) 8)
7 14 35 4
19 27 17 18
9) 10) 11) 12)
8 4 6 7
44 5 15 17
13) 14) 15) 16)
21 6 7 15
10 29 27 47
17) 18) 19) 20)
3 14 28 14