SOLUTION: A motorboat can travel upstream on a river at 12 mph and downstream at 20 mph. How far upstream can the boat travel if it leaves at 8:00 am and must return by noon?
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Question 351783: A motorboat can travel upstream on a river at 12 mph and downstream at 20 mph. How far upstream can the boat travel if it leaves at 8:00 am and must return by noon? Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website! A motorboat can travel upstream on a river at 12 mph and downstream at 20 mph.
How far upstream can the boat travel if it leaves at 8:00 am and must return by noon?
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From the information given we know we have to complete the round trip in 4 hrs
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Let d = one way distance
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Write a time equation: time = dist/speed
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Time up + time down = 4 hrs + = 4
Clear the denominators multiply by 60
60* + 60* = 60(4)
Cancel the denominators and you have:
5d + 3d = 240
8d = 240
d =
d = 30 miles up-stream to return at noon
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Confirm this, find the times + =
2.5 + 1.5 = 4hrs
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That was pretty easy, right?
