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A motorboat travels 116 kilometers in 4 hours going upstream. It travels 164 kilometers going downstream in the same amount of time. What is the rate of the

boat in still water and what is the rate of the current?
Rate of the boat in still water:
Rate of the current:

User Technomage
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1 Answer

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Answer:

  • boat: 35 km/h
  • current: 6 km/h

Explanation:

Let b and c represent the rates of the boat and current, respectively. Then the upstream rate is ...

speed = distance/time

b -c = (116 km)/(4 h) = 29 km/h

b +c = (164 km)/(4 h) = 41 km/h

Adding these equations gives ...

2b = 70 km/h

b = 35 km/h

Substituting into the first equation, we have ...

35 -c = 29

c = 6

Rate of the boat: 35 km/h.

Rate of the current: 6 km/h

User Snurre
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