192 has factors of 1, 2, 3, 4, 6, 8, 12, 16, 24, 32, 48, 64, 96, and 192. The factors of 171 are 1, 3, 9, 19, 57 and 171. Their common factors are therefore 1 and 3.
192 divided by 4 is 48.
4.0714
96
3.6226
24
3
192
3.42
1.7812
11.2941
42.75
171 divided by 2 is 85.5