document.write( "Question 810058: The current of a river is 4 miles per hour. A boat travels to a point 30 miles upstream and back in 4 hours. What is the speed of the boat in still water?\r
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Algebra.Com's Answer #487928 by josmiceli(19441) $\"\"$ $\"About$

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Since the current reduces the boat's speed in
\n" ); document.write( "one direction and increases the speed by the
\n" ); document.write( "same amount in the opposite direction,
\n" ); document.write( "you can disregard the effect of the current
\n" ); document.write( " $\"+d+=+r%2At+\"$
\n" ); document.write( " $\"+30+%2B+30+=+r%2A4+\"$
\n" ); document.write( " $\"+60+=+4r+\"$
\n" ); document.write( " $\"+r+=+15+\"$
\n" ); document.write( "The speed of the boat in still water is 15 mi/hr
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