Answer :
12 men, 5 days.
If you divide the amount of laborers by 4, you must multiply the time it takes by 4. Thus 12/4=3 men and 5*4= 20 days.
If you divide the amount of laborers by 4, you must multiply the time it takes by 4. Thus 12/4=3 men and 5*4= 20 days.