Answer: common difference = -5
Explanation:
This is an arithmetic progression. The common difference will be gotten by subtracting the 1st term from the 2nd term. This will be:
1st term = 12
2nd term = 7
3rd term = 2
Common difference = 7 - 12 or 2 - 7 = -5
It isn't an geometric progression as the ratio isn't thesame
= 2nd term / 1st term
= 7/12
= 3rd term / 2nd term
= 2/7
Therefore, it's an arithmetic progression with difference of -5