Question 1205975
<pre>
              WORK RATE        TIME          JOBS

JOSH            1/3              3             1

KEN             1/7              7             1

COMBINED    {{{1/3+1/7}}}----the two of them working together
</pre>
{{{1/3+1/7}}}

{{{(7+3)/21}}}

{{{10/21}}}

Or 21 hours to do 10 jobs;  


About 2 hours 6 minutes to do 1 job