document.write( "Question 581626: The speed of a stream is 5 mph. If a boat travels 94 miles downstream in the same time it takes to travel 47 miles upstream what is the speed of the boat in still water?
\n" ); document.write( "Please explain step by step. \n" ); document.write( "

Algebra.Com's Answer #371751 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
Let $\"+s+\"$ = the speed of the boat in still water
\n" ); document.write( " $\"+s+%2B+5+\"$ = speed of boat going downstream
\n" ); document.write( " $\"+s+-+5+\"$ = speed of boat going upstream
\n" ); document.write( "Let $\"+t+\"$ = time going both upstream and downstream
\n" ); document.write( "----------
\n" ); document.write( "Going downstream:
\n" ); document.write( "(1) $\"+94+=+%28+s+%2B+5+%29%2At+\"$
\n" ); document.write( "Going upstream:
\n" ); document.write( "(2) $\"+47+=+%28+s+-+5+%29%2At+\"$
\n" ); document.write( "-----------------
\n" ); document.write( "(1) $\"+94+=+s%2At+%2B+5t+\"$
\n" ); document.write( "(2) $\"+47+=+s%2At+-+5t+\"$
\n" ); document.write( "------------------
\n" ); document.write( "Subtract (2) from (1)
\n" ); document.write( "(1) $\"+94+=+s%2At+%2B+5t+\"$
\n" ); document.write( "(2) $\"+-47+=+-s%2At+%2B+5t+\"$
\n" ); document.write( " $\"+47+=+10t+\"$
\n" ); document.write( " $\"+t+=4.7+\"$ hrs
\n" ); document.write( "and
\n" ); document.write( "(1) $\"+94+=+%28+s+%2B+5+%29%2A4.7+\"$
\n" ); document.write( "(1) $\"+94%2F4.7+=+s+%2B+5+\"$
\n" ); document.write( "(1) $\"+20+=+s+%2B+5+\"$
\n" ); document.write( "(1) $\"+s+=+15+\"$
\n" ); document.write( "The speed in still water is 15 mi/hr
\n" ); document.write( "check answer:
\n" ); document.write( "(2) $\"+47+=+%28+15+-+5+%29%2At+\"$
\n" ); document.write( "(2) $\"+47+=+10t+\"$
\n" ); document.write( "(2) $\"+t+=4.7+\"$
\n" ); document.write( "OK \n" ); document.write( "

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