document.write( "Question 208299: The speed of a stream is 3 mph. A boat travels 4 miles upstream in the same time it takes it to travel 10 miles downstream.\r
\n" ); document.write( "\n" ); document.write( "What is the speed of the boat in still water?
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Algebra.Com's Answer #157591 by checkley77(12844)\"\" \"About 
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D=RT
\n" ); document.write( "T=D/R
\n" ); document.write( "T=4/(R-3)
\n" ); document.write( "T=10/(R+3)
\n" ); document.write( "4/(R-3)=10/(R+3)
\n" ); document.write( "10(R-3)=4(R+3)
\n" ); document.write( "10R-30=4R+12
\n" ); document.write( "10R-4R=12+30
\n" ); document.write( "6R=42
\n" ); document.write( "R=42/6
\n" ); document.write( "R=7 MPH IS THE SPEED OF THE BOAT.
\n" ); document.write( "PROOF:
\n" ); document.write( "4/(7-4)=10/(7+3)
\n" ); document.write( "4/4=10/10
\n" ); document.write( "1=1\r
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