SOLUTION: Jeff can paddle his canoe 30 miles with bran flour home downstream in 2 hours. On his trip back home, he paddles upstream and it takes 6 hours. What is the rate of the current?
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-> SOLUTION: Jeff can paddle his canoe 30 miles with bran flour home downstream in 2 hours. On his trip back home, he paddles upstream and it takes 6 hours. What is the rate of the current?
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Question 134885: Jeff can paddle his canoe 30 miles with bran flour home downstream in 2 hours. On his trip back home, he paddles upstream and it takes 6 hours. What is the rate of the current?
A. 5 mi/h
B. 10 mi/h
C. 15 mi/h
D. 20 mi/h Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! Jeff can paddle his canoe 30 miles with bran flour home downstream in 2 hours. On his trip back home, he paddles upstream and it takes 6 hours. What is the rate of the current?
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Let the current rate be "c"; let boat speed in still water be "b":
Downstream DATA:
Distance = 30 miles; Time= 2 hrs; Rate = 30/2 = 15mph
Upstream DATA:
Distance = 30 miles ; Time = 6 hrs; Rate = 30/6)= 5 mph
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EQUATIONS
b+c = 15
b-c = 5
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Add to solve for "b":
2b = 20
b = 10 mph
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Substitute to solve for "c":
10+c = 15
c = 5 mph (this is the speed of the current)
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Cheers,
Stan H.
A. 5 mi/h
B. 10 mi/h
C. 15 mi/h
D. 20 mi/h
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