Question 1132109
A person is rowing downstream, and drinking vodka as he rows.  As he passes under a bridge, the bottle falls into the water.  He doesn't notice, because he has drunk 1/2 the bottle.  Because the bottle is 1/2 empty, it floats.
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He rows for 20 minutes, then finds the bottle is missing.  He turns around and rows upstream and meets the bottle 1 mile from the bridge.
What's the speed of the current?
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The boat and the bottle are in the same medium, the water.
Instead of a stream, imagine the event in open water, and bottle falls in near a buoy and the man rows away from it for 20 minutes.
Obviously, it takes 20 minutes to return.
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The bottle moves 1 mile in 40 minutes --> 1.5 mi/hr current.
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"classic version in rectified form" ???  What does that mean?