Five men working 9 hrs for a day can complete the work in 16 days. How many days would 8 men take if they do the work 10 hours per day ?

Question

It is a question from go maths chapter direct and inverse proportion please help me if anyone knows th answer

Answer 1

The job takes 720 man hours (5 * 9 * 16)

With 80 man hours (8 * 10) per day they would need 9 days (720 / 80).