Question

Math on the Spot Find the GCF of each set of numbers.

5. 8 and 12
6. 10, 15, and 30
7. 18, 36, and 60

Answer 1

5. The factors of 8 are 1, 2, 4, and 8. The factors of 12 are 1, 2, 3, 4, 6, and 12. The greatest common factor (GCF) is 4.

6. The factors of 10 are 1, 2, 5, and 10. The factors of 15 are 1, 3, 5, and 15. The factors of 30 are 1, 2, 3, 5, 6, 10, 15, and 30. The GCF is 5.

7. The factors of 18 are 1, 2, 3, 6, 9, and 18. The factors of 36 are 1, 2, 3, 4, 6, 9, 12, 18, and 36. The factors of 60 are 1, 2, 3, 4, 5, 6, 10, 12, 15, 20, 30, and 60. The GCF is 6.