Adding Fractions with Unlike Denominators Practice

Every problem has two different denominators, such as 3/4 + 2/5. Best for Grade 5 (Common Core 5.NF.A.1).

Ready-to-use practice

12 sample questions

A ready-made set at the starting difficulty. Check each one against the sample answers below.

  1. 4/11 + 1/2 = ?
  2. 1/11 + 2/3 = ?
  3. 1/3 + 5/12 = ?
  4. 4/9 + 2/3 = ?
  5. 6/11 + 1/2 = ?
  6. 3/4 + 1/2 = ?
  7. 2/3 + 8/11 = ?
  8. 2/3 + 4/11 = ?
  9. 1/6 + 3/4 = ?
  10. 1/2 + 2/9 = ?
  11. 1/6 + 4/5 = ?
  12. 5/12 + 4/9 = ?
Show sample answers
  1. 4/11 + 1/2 = 19/22
  2. 1/11 + 2/3 = 25/33
  3. 1/3 + 5/12 = 3/4
  4. 4/9 + 2/3 = 1 1/9
  5. 6/11 + 1/2 = 1 1/22
  6. 3/4 + 1/2 = 1 1/4
  7. 2/3 + 8/11 = 1 13/33
  8. 2/3 + 4/11 = 1 1/33
  9. 1/6 + 3/4 = 11/12
  10. 1/2 + 2/9 = 13/18
  11. 1/6 + 4/5 = 29/30
  12. 5/12 + 4/9 = 31/36

How to solve it

3/4 + 2/5 = 1 3/20

A common denominator of 4 and 5 is 20. 3/4 = 15/20 and 2/5 = 8/20, so the sum is 23/20 = 1 3/20.

Tip: Never add the denominators: 1/2 + 1/3 is 5/6, not 2/5. Rewrite both fractions over a common denominator first, then add only the numerators.

Best for Grade 5 · Common Core 5.NF.A.1 · How MathFun makes these questions

What each level covers

Each level changes the kind of problem, not the grade. Pick the level that matches what is being learned, then open a practice set at that level.

  1. Level 1: Like denominators

    Example: 2/7 + 3/7

  2. Level 2: Like denominators, mixed numbers

    Example: 2 3/8 + 1 7/8

  3. Level 3: Related denominators

    Example: 1/3 + 5/6

  4. Level 4: Unlike denominators

    Example: 3/4 + 2/5

  5. Level 5: Mixed numbers, unlike denominators

    Example: 2 1/3 + 1 3/4

  6. Level 6: Improper fractions · Challenge

    Example: 7/4 + 11/6

  7. Level 7: Denominators up to 20 · Challenge

    Example: 7/16 + 5/12

  8. Level 8: Mixed numbers, denominators up to 20 · Challenge

    Example: 3 5/16 + 2 7/12

  9. Level 9: Two-digit fractions, related denominators · Challenge

    Example: 57/32 + 3/16

  10. Level 10: Two-digit fractions, unlike denominators · Challenge

    Example: 35/24 + 17/18