Question 488178
20 men, 20 days, 1/3 work=1/20x1/20x1/3=1/1200 the amount of the work one man does in one day.
To finish 2/3 the work in 25 days is 2/3x1/25=2/75 work needs to be done each day
n/1200=2/75
75n=2400
n=2400/75=32 men
Since you already have 20 men, you need to hire 12 more to finish the job on time..