SOLUTION: I dont even know where to start with this problem. The boat can travel 112 miles downstream in 4 hours but requires 6 hours to travel 48 miles upstream. What is the speed of the b
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Question 306764: I dont even know where to start with this problem. The boat can travel 112 miles downstream in 4 hours but requires 6 hours to travel 48 miles upstream. What is the speed of the boat in still water, and what is the speed of the current? Answer by dabanfield(803) (Show Source):
You can put this solution on YOUR website! I dont even know where to start with this problem. The boat can travel 112 miles downstream in 4 hours but requires 6 hours to travel 48 miles upstream. What is the speed of the boat in still water, and what is the speed of the current?
We will need to use the formula distance = speed*time (d=s*t). Let c be the speed of the current and b the speed the speed the boat can travel in still water. The speed going downstream (with the current) is b+c and the speed going upstream (against the current ) is b-c. We have two equations:
Upstream:
d = s*t
48 = (b-c)* 6
Divide both sides above by 6:
8 = b - c
1.) b = 8 + c
Downstream:
d = s*t
112 = (b+c) * 4
Divide both sides above by 4:
2.) 28 = b + c
Substituting 8 + c for b (from 1.) in equation 2.) we have:
28 = (8 + c) + c
28 = 8 + 2*c
2*c = 20
c = 10
Sustituting 10 for c in 1.) we have b = 8 + 10 = 18.
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