    1. What are the common factors of 14 and 28? The factors of 14 are 1, 2, 7 and 14 The factors of 28 are 1, 2, 4, 7, 14 and 28 So the common factors 14 and 28 are 1, 2, 7 and 14

 2. What are the common factors of 16 and 32? The factors of 16 are 1, 2, 4, 8 and 16 The factors of 32 are 1, 2, 4, 8, 16 and 32 So the common factors of 16 and 32 are 1, 2, 4, 8 and 16

 3. What are the common factors of 18 and 40? The factors of 18 are 1, 2, 3, 6, 9 and 18 The factors of 40 are 1, 2, 4, 5, 8, 10, 20 and 40 So the common factors of 18 and 40 are 1 and 2

 4. What are the common factors of 8 and 24? The factors of 8 are 1, 2, 4 and 8 The factors of 24 are 1, 2, 3, 4, 6, 8, 12 and 24 So the common factors of 8 and 24 are 1, 2, 4 and 8

 5. What are the common factors of 15 and 18? The factors of 15 are 1, 3, 5 and 15 The factors of 18 are 1, 2, 3, 6, 9 and 18 So the common factors of 15 and 18 are 1 and 3

 6. What are the common factors of 20 and 32? The factors of 20 are 1, 2, 4, 5, 10 and 20 The factors of 32 are 1, 2, 4, 8, 16 and 32 So the common factors of 20 and 32 are 1, 2 and 4

 7. What are the common factors of 18 and 30? The factors of 18 are 1, 2, 3, 6, 9 and 18 The factors of 30 are 1, 2, 3, 5, 6 , 10, 15 and 30 So the common factors of 18 and 30 are 1, 2, 3 and 6

 8. What are the common factors of 15, 24 and 30? The factors of 15 are 1, 3, 5 and 15 The factors of 24 are 1, 2, 3, 4, 6, 8, 12 and 24 The factors of 30 are 1, 2, 3, 5, 6, 10, 15 and 30 So the common factors of 15, 24 and 30 are 1 and 3 back to:   