Question 1052639
Constant Work-Rates Rule,  R*T=J
R is rate in JOBS/TIME;
T is Time;
J is how many jobs.



Combined work rate for two agents working on the same job is the SUM of the individual rates.


Tabulating the given information can often help.


<pre>
                RATE        TIME          JOB Quantity

Laura            1/5         5             1

Bill             r                      
 
Combined        1/3          3             1                   

</pre>
This helps to find Bill's rate.
{{{highlight_green(1/5+r=1/3)}}}

{{{r=1/3-1/5}}}

{{{r=5/15-3/15}}}

{{{highlight_green(r=2/15)}}}-------Bill's rate in jobs per hour.



Now you want to calculate HOW MUCH of the job did each Bill and Laura do, when they worked together for that three hours.
-
<b>Bill:</b>  {{{(2/15)(jobs/hours)*3(hours)=highlight((2/5)*job)}}}

<b>Laura:</b>  {{{(1/5)(jobs/hours)*3(hours)=highlight((3/5)*job)}}}
-


You can try to check this.  The sum of those two PARTS of the 1 job should be 1.
{{{2/5+3/5=5/5=1}}}, so this seems sensible.


You can change these to percents if you want.