The fisherman reaches the town on 4th day.
SOLUTION:
Given, A fisherman rows his boat toward a town 17 miles upstream.
Each day he rows the boat 6 miles upstream, and each night the boat drifts back 2 miles.
We have to find If this pattern continues on which day will he reach the town?
Now, after 1st day distance between him and town = 17 – 6 = 11 miles
And after that night, distance = 11 + 2 = 13 miles
Now, again after 2nd day, distance = 13 – 6 = 7 miles
And after that night, distance = 7 + 2 = 9 miles
Now, again after 3rd day, distance = 9 – 6 = 3 miles
And after the night, distance = 3 + 2 = 5 miles
Now, again after 4th day, distance = 5 – 6 miles = - 1 miles
Here, - 1 miles means that he already reached the town.
Hence, the fisherman reaches the town on 4th day