Using arithmetic sequence concepts, it is found that the common difference is of 0.25.
<h3>What is an arithmetic sequence?</h3>In an arithmetic sequence, the difference between consecutive terms is always the same, called common difference d.
The nth term of an arithmetic sequence is given by:
In which is the first term.
In this problem, we have that:
Hence:
9 = 8 + 4d
4d = 1.
d = 0.25.
The common difference is of 0.25.
More can be learned about arithmetic sequence concepts at brainly.com/question/6561461