Answers

The Brainliest Answer!
2014-11-27T17:00:52+08:00
Let 'x' be the speed of the boat
      'y' be the speed of the current
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-the boat travels 4km in 20min with the current
x + y = 4km/20min
x + y = 0.2km/min       ------equation 1
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-the boat took 24min of travel against the current
x - y = 4km/24min
x - y = 0.1667km/min    ------equation 2
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Add equations 1 and 2
     x + y = 0.2
+  x - y = 0.1667
   2x = 0.3667
      x = 0.18333 km/min
     x = 183.33 m/min
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substitute x=1.08333 to equation 1
x + y = 0.2
y = 0.2 - x
y = 0.2 - 0.18333
y = 0.01667km/min
y = 16.67 m/min
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Therefore the speed of the boat is 183.33 m/min and the speed of the current is 16.67 m/min.
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