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
Answer:
10 feet
Step-by-step explanation:
Let
x----------> the first mechanic rates
y----------> the second mechanic rates
we know that
x+y=165
15x+5y=1775
using a graph tool
see the attached figure
the solution is
x=95
y=70
the answer is
the rates of the first mechanic is 95the rates of the second mechanic is 70
We need to calculate a TIME. Here, TIME = job / rate
Here,
1 JOB 1 1
------------------------------------- = ------------------ = ---------------
JOB/5 min + JOB/15 min 1/5 + 1/15 3/15+1/15
1
= ------------ minutes = 15/4 minutes = 3 3/4 minutes (answer)
4/15