Answer:
1.) 10: 1, 2, 5, 10.
15: 1, 3, 5, 15,
Answer would be 5.
2.) 18: 1, 2, 3, 6, 9, 18
21: 1, 3, 7, 21
Answer would be 3.
3.) 12: 1, 2, 3, 4, 6, 12.
24: 1, 2, 3, 4, 6, 8, 12, 24.
Answer would be 12.
4.) 8: 1, 2, 4, 8.
20: 1, 2, 4, 5, 10, 20.
Answer would be 4.
5.) 14: 1, 2, 7, 14.
28: 1, 2, 4, 7, 14, 28.
Answer would be 14.
Explanation:
Using the listing method, you would first list the common factors of each number, to which that number could be multiplied by. Then, you would search for the greatest common factor.