Answer:
4 days
Step-by-step explanation:
The trick here is to keep in mind that the amount of time taken to plough the field is inversely proportional to the number of ploughmen
That means the more the number of ploughmen, the shorter the time taken
In general time taken to complete a task is inversely proportional to the size of manpower. More hands at work means less time taken
We are given
2 ploughmen can plough the field in 10 days
That means one ploughman working alone will take twice as much = 2 x 10 = 20 days to plough the same field
If there are 5 ploughmen, the efforts of a single ploughman are reduced by one-fifth.
Therefore with 5 ploughmen, it will take 20/5 = 4 days to plough the field if they all work at the same rate
