SOLUTION: a motor boat goes 5 miles upstream in the same time it requires to go 7 miles downstream. if the river flows at 2 mph, find the speed of the boat in still water.
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Question 289377: a motor boat goes 5 miles upstream in the same time it requires to go 7 miles downstream. if the river flows at 2 mph, find the speed of the boat in still water. Answer by mananth(16946) (Show Source):
You can put this solution on YOUR website! Let the speed of the boat be x mph in still water
upstream the speed will be x-2 mph
downstream the speed will be x+2
time taken both ways is the same. ( distance / speed = time)
5/x-2 =7/ x+2
5(x+2)=7(x-2)
5x+10=7x-14
-2x=-24
x=12 mph
