Based on the total cost that Juan incurred to hire the roofer including the charge for parts and labor, the number of hours that was needed to complete the job was 14.50 hours.
The first thing to do is to find out the amount that went to labor:
= Final bill - cost of materials
= 1,131.5 - 450
= $681.50
Now that you have the cost of labor, you can find out the number of labor hours that were used based on the hourly rate:
= Cost of labor / Hourly rate
Solving gives:
= 681.50 / 47
= 14.5 hours
In conclusion, the number of labor hours that the roofer used to complete the work, based on the total amount charged to Juan is 14.50 hours.
Find out more on job cost per hour at https://brainly.com/question/3726490.
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