>28 is the correct number. Congrats to Ed, Sharon and Dan. If 1.5 men can do 1.5 roads in 1.5 days, then 1.5 men do (1.5 Roads divided by 1.5 Days) 1 Road Per Day
This stands to reason: if 1.5 men do one road in one day then obviously they would do another half a road in half a day (1.5 men = 1.5 Roads = 1.5 Days, per the question). In a problem solving world
6 men would do 4 times as much work as 1.5 men (6 divided by 1.5 = 4) in the same time period. Hence, 6 men would do 4 roads per day.
If 6 men work for 7 days then they will do 28 Roads (4 roads per day times 7 days).