Question 413303
An experienced bricklayer can work twice as fast as an apprentice bricklayer.
 After they worked 8 hrs. the experienced one quit.
 The apprentice required 12 more hrs to finish the job.
How long would it take the experienced one, working alone, to do the job?
:
Let t = experienced bricklayer's time alone to do the job
it says,"An experienced bricklayer can work twice as fast as an apprentice bricklayer."therefore
2x = apprentice time working alone
:
Let the completed job = 1
:
A typical shared work equation
The apprentice worked a total of: 8 + 12 = 20 hrs
{{{8/x}}} + {{{20/(2x)}}} = 1
multiply eq by 2x, results
2(8) + 20 = 2x
16 + 20 = 2x
36 = 2x
x = {{{36/2}}}
x = 18 hr for the experience guy to do the job
:
;
Check solution
8/18 + 20/36 = 
4/9 + 5/9 =1