SOLUTION: The speed of a stream is 5 mph. If a boat travels 86 mi downstream in the same time that it takes to 18) travel 43 mi upstream, what is the speed of the boat in still water?
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Question 769209: The speed of a stream is 5 mph. If a boat travels 86 mi downstream in the same time that it takes to 18) travel 43 mi upstream, what is the speed of the boat in still water? Answer by Cromlix(4381) (Show Source):
You can put this solution on YOUR website! Speed of boat = x
86/x + 5 = 43/x - 5
Cross multiply
86(x - 5) = 43(x + 5)
86x - 430 = 43x + 215
86x - 43x = 215 + 430
43x = 645
x = 15
Speed of boat = 15mph
Hope this helps.
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