Question 1067383:  Two workers and B together could finish a work in 8 days. They worked together for 6 days and A left the work. The remaining work was completed by B alone in 6 days. How many days would each take to complete the work individually ?  
 Answer by KMST(5328)      (Show Source): 
You can  put this solution on YOUR website! What we have to find is 
 = number of days that it would take worker A to complete the job by himself (or herself), 
and 
 = number of days needed for B to complete the job working alone. 
In one day of work, the fraction of the job that 
A would complete is   , 
and the fraction of the job B would complete 
is   . 
Working together, they would complete 
  of the job each day, 
and that would be   of the job. 
(You could also say that 
  ), 
but either way, you end up with 
  . 
  is the fraction of the job 
that A and B complete, working together, 
during the first 6 days. 
  is the fraction of the whole job 
that B does all alone, during the next 6 days. 
After that, the fraction of the job that has been completed is 
  or   . 
We solve that to find   : 
Multiplying both sides of the equal sign times   
we get the equivalent equation 
  
  
  . 
Now, substituting the value for   
into   , 
we get   , 
which we solve for   . 
First, we multiply both sides of the equal sign 
times   to get the equivalent equation 
  
  
  
  
  
  . 
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