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Greatest factor, least multiple: 6th grade math

GCF and LCM. A free 6th 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: gCF and LCM.

Teach (10 min)

  • A factor divides a number with nothing left. A common factor divides two numbers.
  • Factors of 36 and 48 that match: 1, 2, 3, 4, 6, 12. The greatest is 12.
  • 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/base10.gcf?lesson=6-base10-gcf-1&at=6

Exit ticket (5 min)

  • Three questions on a slip:
  • 1. What is the greatest common factor (GCF) of 12 and 10?
  • 2. What is the greatest common factor (GCF) of 20 and 30?
  • 3. What is the greatest common factor (GCF) of 4 and 12?

Question set

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

  1. What is the greatest common factor (GCF) of 12 and 10?
  2. What is the greatest common factor (GCF) of 20 and 30?
  3. What is the greatest common factor (GCF) of 4 and 12?
  4. What is the greatest common factor (GCF) of 8 and 12?
  5. What is the greatest common factor (GCF) of 15 and 18?
  6. What is the greatest common factor (GCF) of 20 and 30?
  7. What is the greatest common factor (GCF) of 108 and 24?
  8. What is the greatest common factor (GCF) of 60 and 72?
  9. What is the greatest common factor (GCF) of 77 and 66?
  10. What is the greatest common factor (GCF) of 18 and 45?
Answers
  1. 2
  2. 10
  3. 4
  4. 4
  5. 3
  6. 10
  7. 12
  8. 12
  9. 11
  10. 9

Printable sheet

Name: ____________________   Date: ____________

Greatest factor, least multiple (6th grade)

  1. What is the greatest common factor (GCF) of 24 and 18?
  2. What is the greatest common factor (GCF) of 9 and 15?
  3. What is the greatest common factor (GCF) of 9 and 12?
  4. What is the greatest common factor (GCF) of 12 and 8?
  5. What is the greatest common factor (GCF) of 80 and 50?
  6. A florist has 40 roses and 32 tulips. She makes identical bouquets with no flowers left over. What is the greatest number of bouquets?
  7. A teacher has 6 pencils and 9 erasers to put in identical kits with none left over. What is the most kits that can be made?
  8. What is the greatest common factor (GCF) of 136 and 102?
  9. A baker has 112 muffins and 84 cookies to pack in identical boxes with nothing left over. What is the most boxes?
  10. What is the greatest common factor (GCF) of 108 and 72?
  11. What is the greatest common factor (GCF) of 126 and 90?
  12. What is the greatest common factor (GCF) of 63 and 14?
Key
  1. 6
  2. 3
  3. 3
  4. 4
  5. 10
  6. 8
  7. 3
  8. 34
  9. 28
  10. 36
  11. 18
  12. 7

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.