Respuesta :
The number of hours he need to work is 4.
Given that,
- Sam charges a $5 travel free and then 3.25 per hour for labor.
- The earnings is $18.
- Here we assume the no of hours be x.
Based on the above information, the calculation is as follows:
5 + 3.25x = 18
3.25x = 18 - 5
3.25x = 13
x = 4
Learn more: brainly.com/question/17429689