a man rows downstream for one hour and 40 minutes on a river flowing at 2 miles per hour. on his returned trip he rows upstream for 5hours. find the distance that he traveled downstream and his speed of rowing in still water.

Answer 1

since the distance down and up is the same, if the boat's still-water speed is s,

5/3 (s+2) = 5(s-2)
s = 4

so, he rows at 4 mph in still water
the distance is thus 10 miles