Question

A man can do a work in 20 days and a woman can do it in 30 days. Men worked

Answer 1

Man can do a work in 20days
work of a men in one day=1/20.
work of a women =30days
women work in one day=1/30.
Men work =1/20-1/30
3-2/60=1/60
So work of men in one day =60days.