SOLUTION: A roofer requires 8 h to shingle a roof. After the roofer and an apprentice work on a roof for 2 h, the roofer moves on to another job. The apprentice requires 16 more hours to fin
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-> SOLUTION: A roofer requires 8 h to shingle a roof. After the roofer and an apprentice work on a roof for 2 h, the roofer moves on to another job. The apprentice requires 16 more hours to fin
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Question 750637: A roofer requires 8 h to shingle a roof. After the roofer and an apprentice work on a roof for 2 h, the roofer moves on to another job. The apprentice requires 16 more hours to finish the job. How long would it take the apprentice, working alone, to do the job Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website! A roofer requires 8 h to shingle a roof.
After the roofer and an apprentice work on a roof for 2 h, the roofer moves on to another job.
The apprentice requires 16 more hours to finish the job.
How long would it take the apprentice, working alone, to do the job
:
let a = time required by the apprentice to do the job alone
Let the completed job = 1
:
A typical shared work equation
Each will do a fraction of the job, the two fractions have to add up to 1
The apprentice worked a total 18 hr + = 1
mult eq by 8a, cancel the denominators and you have
2a + 8(18) = 8a
144 = 8a - 2a
144 = 6a
a = 144/6
a = 24 hrs for the apprentice alone
:
:
Check this + =
.25 + .75 = 1
