SOLUTION: Two boats start at the same place on a river and travel in opposite directions. The boat going downriver travels 4 miles per hour faster than the boat traveling upriver. If after 5

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Question 1028644: Two boats start at the same place on a river and travel in opposite directions. The boat going downriver travels 4 miles per hour faster than the boat traveling upriver. If after 5 hours they are 470 miles apart, how fast was each boat traveling?
Answer by mananth(16946) About Me  (Show Source):
You can put this solution on YOUR website!
Two boats start at the same place on a river and travel in opposite directions. The boat going downriver travels 4 miles per hour faster than the boat traveling upriver. If after 5 hours they are 470 miles apart, how fast was each boat traveling?

upstream boat speed in still water =x
downstream boat in still water = x+4
The resultant speed will be 2x+4
Since both are travelling away from each other the effective speed will also be 2x+4
t=d/r
5= 470/(2x+4)
10x+20=470
x+2=47
x=45
45mph & 49mph are the speeds