7, 14 and 21
132, 156 and 204
4 and 24 is one such pair.
That happens when one of the numbers is a factor of the other.
Numbers whose only common factor is 1.
29 and 4147
this is hard
12 and 20
There are several possibilities of pairs of numbers whose greatest common factor is 18. 54 and 198 18 and 126 414 and 846 72 and 1422
14 and 28 are two even numbers between 10 and 30 whose greatest common factor is 14.
The GCF is 16.
Any two (or more) numbers whose only common factor is 1.
16 and 8