Greatest common factor, least common multiple

Answer Key - Grade 6 Math Worksheet - Building Confidence

Circle the best answer, or write your answer on the line.

1. 1.

   Jun finds a hint in a book. Multiples of 4: 4, 8, 12, 16. Multiples of 6: 6, 12, 18. What is the least common multiple of 4 and 6?

   12
2. 2.

   Luz solves a number puzzle. Multiples of 3: 3, 6, 9, 12, 15. Multiples of 4: 4, 8, 12, 16. What is the least common multiple of 3 and 4?

   12
3. 3.

   Milo follows a map clue. Multiples of 4: 4, 8, 12, 16, 20, 24, 28. Multiples of 10: 10, 20, 30. What is the least common multiple of 4 and 10?

   20
4. 4.

   Zee finds a hint in a book. What is the least common multiple of 6 and 10?

   30
5. 5.

   Ari races the clock on a number puzzle. What is the least common multiple of 3 and 8?

   24
6. 6.

   Jun has 12 pencils and 28 erasers for the class. Jun puts them into identical supply bags with none left over. What is the greatest number of bags Jun can fill?

   4
7. 7.

   Pia factors a sum. The greatest common factor of 10 and 15 is 5. 10 + 15 = 5(2 + 3). What number goes in the blank?

8. 8.

   Tala factors a sum. The greatest common factor of 18 and 27 is 9. 18 + 27 = 9(2 + 3). What number goes in the blank?

9. 9.

   Ari picks a card. Which expression is 18 + 30 with the greatest common factor taken out?

   • 9(2 + 30)
   • 2(9 + 15)
   • 6(3 + 5)
10. 10.

    Bo picks a card. Which expression is 20 + 32 with the greatest common factor taken out?

    • 4(5 + 8)
    • 2(10 + 16)
    • 5(4 + 32)