Skip to the content
Peabody TeachFor teachers and grown-ups

Add different denominators: 5th grade math

Add/subtract unlike denominators via equivalent fractions, including mixed numbers. A free 5th grade lesson plan, a question set with answers and a printable sheet with its key. Copy it and make it yours.

Lesson plan

Goal

  • Students can do this: add/subtract unlike denominators via equivalent fractions, including mixed numbers.

Teach (10 min)

  • Halves and thirds are different-size pieces. Rename both over a bottom they share first.
  • 1/2 = 3/6 and 1/3 = 2/6, so 1/2 + 1/3 = 5/6.
  • Work one example on the board while students say each step aloud, then do one together.

Practise (15 min)

  • Students work the printable sheet in pairs, then alone.
  • Or practise it as a game with no sign-up: https://peabody.kids/math/commonDenominator.addUnlike?lesson=5-add-unlike&at=5

Exit ticket (5 min)

  • Three questions on a slip:
  • 1. Add the two fractions: 7/10 + 1/4
  • 2. Add the two fractions: 11/12 + 1/6
  • 3. Add the two fractions: 3/4 + 5/8

Question set

10 questions that read in words, easiest first. Questions that need a picture are on the printable sheet below.

  1. Add the two fractions: 7/10 + 1/4
  2. Add the two fractions: 11/12 + 1/6
  3. Add the two fractions: 3/4 + 5/8
  4. Add the two fractions: 1/2 + 3/4
  5. Add the two fractions: 3/10 + 3/4
  6. Add the two fractions: 1/2 + 2/5
  7. Add the two fractions: 7/12 + 2/3
  8. Add the two fractions: 5/6 + 1/5
  9. Add the two fractions: 7/12 + 1/6
  10. Add the two fractions: 2/5 + 5/8
Answers
  1. 19/20
  2. 11/12
  3. 13/8
  4. 11/4
  5. 11/20
  6. 9/10
  7. 11/4
  8. 11/30
  9. 3/4
  10. 11/40

Printable sheet

Name: ____________________   Date: ____________

Add different denominators (5th grade)

  1. Add the two fractions: 25 + 110
  2. Add the two fractions: 12 + 1112
  3. Add the two fractions: 13 + 16
  4. Add the two fractions: 58 + 56
  5. Add the two fractions: 35 + 38
  6. Add the two fractions: 710 + 12
  7. Add the two fractions: 12 + 310
  8. Add the two fractions: 78 + 34
  9. Add the two fractions: 310 + 16
  10. Add the two fractions: 13 + 12
  11. Add the two fractions: 23 + 12
  12. Add the two fractions: 12 + 13
Key
  1. 12
  2. 1512
  3. 12
  4. 11124
  5. 3940
  6. 115
  7. 45
  8. 158
  9. 715
  10. 56
  11. 116
  12. 56

Written by Peabody from its own skill pages. Free, no ads, no sign-in. Children can practise this on Peabody. More from teachers: teacher-shared resources.