Question 522450
A roofer requires 10 h to shingle a roof.
 After the roofer and an apprentice work on a roof for 6 h, the roofer moves on to another job.
 The apprentice requires 8 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
Let the completed job = 1
:
From the given information, we know the roofer worked 6 hrs, the apprentice 14 hrs
:
Write a shared work equation
{{{6/10}}} + {{{14/a}}} = 1
multiply 10a, results:
6a + 10(14) = 10a
140 = 10a - 6a
140 = 4a
a = {{{140/4}}}
a = 35 hrs apprentice working alone
:
:
Check this out,
{{{6/10}}} + {{{14/35}}} =
.6 + .4 = 1