A hunter wishes to cross a river that is 1.6 km wide and that flows with a speed of 3.4 km/h. The hunter uses a small powerboat that moves at a maximum speed of 12.4 km/h with respect to the water. What is the minimum time necessary for crossing?
The Attempt at a Solution
I used pythagorean theorem to find the resultant velocity of the water flowing and the speed of the boat:
square root of: 3.4^2+12.4^2= 12.9km/h
Divide width of river by the velocity: 1.6/12.9 = .124hr
Multiply hours by 60 to get mins: .124x60= 7.44 mins
I dont know if i am not getting something right when i'm drawing the picture or if i've understood the problem wrong. Any ideas would be great!