What is the speed of the river in km/hr?

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The discussion focuses on calculating the speed of a river based on a boat's travel times downstream and upstream. The boat travels 15 km downstream in 3.1 hours, resulting in a speed of 4.84 km/hr, and 5.1 hours upstream, yielding a speed of 2.94 km/hr. Participants clarify that the river's speed affects the boat's effective speed, with downstream speeds being the sum and upstream speeds being the difference of the boat's speed and the river's speed. The problem can be approached by setting equations based on these principles to find the river's speed. The conversation emphasizes using the relationship between distance, rate, and time to solve for the unknown.
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a boat takes 3.1 hours to travel 15 km down a river, then takes 5.1 hours to travel the same distance upstream. how fast is the river traveling.

I found the boat is traveling at 4.84km/hr down the stream and 2.94 km/hr up it. not sure where to go next.

Any help would be appreciated.
 
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Let's say the river's speed is 1 kph and the boat's speed is 2 kph then the boat will travel downstream at 3 kph and upstream at 1 kph. So when you go downstream you add the speeds, but when going upstream, you subtract the river's speed from the boat's speed. Try working that backwards.
 

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