it takes 2 hours for a boat to travel 28 miles downstream. The same boat can travel 18 miles upstream in 3 hours. Whats the rate of the streams current ?

Answer 1

distance = rate * time

28 = (r+s) * 2 <--- downstream

18 = (r-s) * 3 <--- upstream

14 = r+s

6 = r-s

20 = 2r

r=10

s=4