Tell whether the sequence is arithmetic. If it is, what is the common difference?
3,7,12,18, ...
The sequence is not arithmetic because there is no constant difference between consecutive terms.
To illustrate this, let's calculate the differences between consecutive terms:
7 - 3 = 4
12 - 7 = 5
18 - 12 = 6
As we can see, the differences are not constant. Therefore, the sequence is not arithmetic and does not have a common difference.