Question 720815
Don Williams uses his small motorboat to go 4 miles upstream to his favorite fishing spot. Against the current, the trip takes 2/5 hours. With the current the trip takes 1/5. How fast can the boat travel in still water. What is the speed of the current??
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1 ? is sufficient.
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Find the speed upstream and downstream using d = r*t.
How fast can the boat travel in still water. (A ? would be good there.)
It's the average of the speed upstream and downstream.
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The speed of the current (called the current) is the difference between the waterspeed and the groundspeed.
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This problem has been posted and solved 1000's of times on this site.  Look it up.