marcus lays a slab of concrete in 7 hrs. tony lays same slab in 3 hrs. if both work on job cost is 41.00 dollars per hr. decide what labor estimate should be

Question

Im confused

Answer 1

First, you'll want to find how long it takes the two to finish laying a slab together.

 

Marcus lays a slab in 7 hours, which is a rate of 1/7 slab per hour. Tony lays a slab in 3 hours, which is a rate of 1/3 slab per hour.

 

Together, then, they lay 1/7 + 1/3 of a slab per hour. That's:

 

1/7 + 1/3 = 3/21 + 7/21 = 10/21 slab per hour

 

At that rate, they'll take x hours to lay (10/21)x slabs. How long will it take to lay 1 slab?

 

1 = (10/21)x

1/x = 10/21

21 = 10x

x = 21/10

x = 2.1 hours

 

For $41 per hour, that's 2.1($41) = $88.20.