1 and 5
80 has 5 factor pairs.
The factor pairs of 215 are 1, 5, 43, and 215
The factor pairs of 10 are 1*10, 2*5
1 and 5
5 and 1
80 has 5 factor pairs.
The factor pairs of 25 are 1 x 25 and 5 x 5
1 and 5 is the only factor pair of 5.
1 and 5
1 and 5
The factor pairs of 15 are 1 x 15 and 3 x 5.
The factor pairs of 205 are 1 x 205 and 5 x 41.