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30 votes
A motorboat travels 464 kilometers in 8 hours going upstream and 644 kilometers in 7 hours going downstream. What is the rate of the boat in still water and what is the rate of the current?

Rate of boat in still water ______km/h

Rate of current: _______ km/h

User Jorge Candeias
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1 Answer

20 votes
20 votes

Let's say you are paddling at 5mph and the current is 3 mph. Going upstream, you are going 2 mph and downstream, 8 mph.

8(b - c) = 464

7(b + c) = 644

b - c = 58

b + c = 92

Adding the two together

2b = 150

b = 75

75 - c = 58

c = 17

The boat's speed is 75 mph and the current's speed is 17 mph.

User Ruxandra
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