Question 142630
I'm presuming that the <b><i> daily</b></i> payroll is $3391.


Let {{{h}}} be the number of heavy equipment operators and {{{g}}} be the number of general laborers.  We are given that {{{h+g=30}}}


Since heavy equipment operators earn $136 per day, the amount of heavy equipment operator payroll is {{{136h}}} per day.  Likewise, the amount of general laborer payroll is {{{81g}}}.  Since the total payroll is {{{3391}}}, we can say {{{136h+81g=3391}}}


Another way to express the first equation is {{{h=30-g}}}.  Now we can combine the two equations by substitution, that is, substitute {{{30-g}}} for {{{h}}} in the second equation, thus:


{{{136(30-g)+81g=3391}}}


Solve this equation for {{{g}}} to get the number of general laborers, then subtract that from 30 to get the number of heavy equipment operators.


The problem you will face once you get the answer is that there is no integer solution to this problem.  The employment agency is going to have a difficult time hiring fractional people.  On the other hand, if you made a typo in the problem statement and actually meant that the general laborers were paid <b><i> $83</b></i> per day, then it works out. (you will need to solve: {{{136(30-g)+83g=3391}}})