2 men and 3 women working 7 hours a day finish a piece of work in 5 days; 4 men and 4 women working 3 hours a day do the same work in 7 days. Find the number of days in which the work is done by 7 men only, working 4 hours a day.
1
5 days
2
4 days
3
6 days
4
3 days