Question 951772
The hours per day for any worker did not change.


Let r be the one-worker rate, JOBS per DAY.
RT=J rate time job


{{{12r*25=1}}} for the basic facts for the original group of twelve.
{{{r=1/(12*25)}}}


The twelve original worked for 5 days, and then the 12-3=9 workers remaining worked for t unknown days to finish the 1 job.
{{{highlight_green(12r*5+9r*t=1)}}}
{{{9rt=1-60r}}}
{{{t=(1-60r)/(9r)}}}
{{{t=(1-60(1/(12*25)))/(9(1/(12*25)))}}}-----simplify this complex fraction for the number of days.



Multiply by {{{(12*25)/(12*25)}}} to start the best simplification steps.


{{{t=(12*25-60)/9}}}


{{{t=(4*25-20)/3}}}


{{{t=80/3}}}

{{{highlight(t=26&2/3)}}}