72 men can build a small house in 30 days, working 8 hours a day. In how many days will 80 men, working 6 hours a day, complete the work?
36 days
Let the required number of days to complete the work be x.
From productivity axiom, we know that
72 × 30 × 8 = 80 × 6 × x
x = 72×30×880×6
x = 36 days