Answer:

6. 8 and 12= 2

9. 56 and 80= 2

7. 9 and 21= 3

10.90 and 240= 2

8. 28 and 42= 2

Answer:

think of factors/numbers that both of the given number have. for example,

1. 8 and 12

using prime factorization, what are the numbers that when multiplied will have answers 8 and 12?

8 : 1,8 ,, 2, 4

12 : 1,12 ,, 6,2 ,, 4,3

find then the greatest factors that both given numbers have. they have both number four and its the greatest, thus you have the gcf of 8 and 12 as 4.

1. 4

2. 8

3. 3

4. 30

5. 14