SOLUTION:
Step 1 :
In the question, we are told that:
Johann has traveled 15 miles from his station on the train.
He will continue on the train at 80 miles per hour.
If he ends up traveling a total of 615 miles,
we are meant to find how much longer did it take him.
Step 2:
Let t represents the time, so that we have the following:
[tex]15\text{ + 80t = 615}[/tex]
Solving this, we have that:
[tex]\begin{gathered} 80t\text{ = 615 - 15} \\ 80\text{ t = 600} \\ \text{Divide both sides by 80, we have that:} \\ t\text{ = }\frac{600}{80} \\ \text{ t}=\text{ 7. 5 hours} \end{gathered}[/tex]
CONCLUSION:
The final answer is 7. 5 hours
