Math
posted by Gracie .
list the common factors for each pair of numbers. Then find the greatest common factor for each pair.
18 and 30, 9 and 25
60 and 45, 23 and 29
49 and 14, 140 and 25
142 and 148, 84 and 105

find each multiplication problem that goes into each number starting with 2 and go up. do that with the other number you are comparing and then compare.
example
36 and 12
36 = 1,2,3,4,6,9,12,18,36 are factors 36
1x36
2x18
3x12
4x9
6
12 = 1,2,3,4,6,12 are factors of 12
1x12
2x6
3x4
now you compare both numbers of their factors
12 = 1,2,3,4,6,12
36 = 1,2,3,4,6,9,12,18,36
find the numbers they have in common which are 1,2,3,4,. then look at which number is greater
the number is 4 
actually i forgot one number the number is actually 6