Question 908123
Assigning Variables and Setting Equation To Solve:


RATES
A, {{{1/40}}}
B, {{{1/60}}}
c, {{{1/c}}}, letting c = how many days the same named c needs to do the job alone.


A works alone for 4 day;
Without A, B and c complete the work in 36 days.


{{{(1/40+1/60)*4+(1/60+1/c)*36=1}}}.
This equation uses the uniform rates rule for doing a job or task, refers to the one job counted as 1.  The rule is RT=J using rate time, and job.  The job to be done in the example was split into two parts... one part for 4 days and the other part for 36 days.


Solve the equation for c.