To solve this problem you must apply the proccedure shown below:
1. Let's call
to the number of equipment operators and
to the numbers of laborers.
2. Based on the information given in the problem above, you can make a system of equation, as following:

3. By applying the method of substitution, you can solve for
from the second equation and substitute it into the first equation to solve for
, as following:

4. Now, substitute the value of
into the second equation to calculate
:

The answer is: 19 equipment operators and 13 laborers.