15 men can build a 500m long wall in 30 days. In how many days can 30 men build a 1.2 km long wall?
Q1. 15 men can build a 500m long wall in 30 days. In how many days can 30 men build a 1.2 km long wall?
Answer: 36 days
Explanation: Man-days per metre = (15×30)/500 = 0.9; for 1200 m with 30 men: days = 1200×0.9/30 = 36 days.