Given that Marucs lays a slab of concrete in 6 hours and Tony lays the same slab in 4 hours. If both work on the job, the number of hours it will take them to lay the slab is given by:
[tex] \frac{1}{t} = \frac{1}{6} + \frac{1}{4} \\ \\ = \frac{2+3}{12} = \frac{5}{12} \\ \\ \Rightarrow t= \frac{12}{5} =2.4\ hours[/tex]
Given that the cost of labor is $44.00 per hour, therefore, the labor estimate should be 2.4 x 44 = $105.60 per slab.