Question 1027451
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Olivia paddles her kayak a average of 4 kilometers per hour on still water. She paddles against the current of a river 
for 5 kilometers, and it takes her 2.5 hours.  {{{highlight(Find_the_speed_of_the_current)}}}.
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<pre>
Let v be the speed of the current.
Then Olivia's speed floating against the current is (4 - v) kilometers per hour.

Hence, the equation  {{{speed}}} = {{{Distance/Time}}}  for Olivia's trip against the current is 

4 - v = {{{5/2.5}}},   or

4 - v = 2.

Therefore, v = 2 {{{km/h}}} is the current' speed.
</pre>

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