Question

Solve the problem as directed. The time it takes to lay a sidewalk of a certain type varies directly as the length and inversely as the number of men working. If eight men take two days to lay 100 feet, how long will three men take to lay 150 feet?

Answer 1

T = k L / N   where k is the constant of variation

2 = k * 100 / 8 
100k =  16
k = 0.16  

so fromula is

T = 0.16L / N

when L = 150 and N = 3 we have

Time taken T = 016* 150 / 3 =  8 days answer

Answer 2

150/18.75=18.75 feet per day
150/18.75=17.14 days