document.write( "Question 829340: Alvin paddled 8 miles upstream in 2 hours. He paddled 16 miles downstream in the same time. Find the speed that Alvin paddled in still water and the speed of the current \n" ); document.write( "

Algebra.Com's Answer #499794 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
Let $\"+s+\"$ = his speed paddling in still water
\n" ); document.write( "Let $\"+c+\"$ = the speed of the current
\n" ); document.write( "----------------
\n" ); document.write( "Paddling upstream:
\n" ); document.write( "(1) $\"+8+=+%28+s+-+c+%29%2A2+\"$
\n" ); document.write( "Paddling downstream:
\n" ); document.write( "(2) $\"+16+=+%28+s%2Bc+%29%2A2+\"$
\n" ); document.write( "---------------------
\n" ); document.write( "(1) $\"+2s+-+2c+=+8+\"$
\n" ); document.write( "(2) $\"+2s+%2B+2c+=+16+\"$
\n" ); document.write( "Add the equations
\n" ); document.write( " $\"+4s+=+24+\"$
\n" ); document.write( " $\"+s+=+6+\"$
\n" ); document.write( "and
\n" ); document.write( "(1) $\"+2s+-+2c+=+8+\"$
\n" ); document.write( "(1) $\"+s+-+c+=+4+\"$
\n" ); document.write( "(1) $\"+6+-+c+=+4+\"$
\n" ); document.write( "(1) $\"+c+=+2+\"$
\n" ); document.write( "Alvin paddled 6 mi/hr in still water
\n" ); document.write( "and the speed of the current is 2 mi/hr
\n" ); document.write( "----------------------------------
\n" ); document.write( "check:
\n" ); document.write( "(2) $\"+16+=+%28+6%2B2+%29%2A2+\"$
\n" ); document.write( "(2) $\"+16+=+16+\"$
\n" ); document.write( "and
\n" ); document.write( "(1) $\"+8+=+%28+6+-+2+%29%2A2+\"$
\n" ); document.write( "(1) $\"+8+=+8+\"$
\n" ); document.write( "OK
\n" ); document.write( " \n" ); document.write( "

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