document.write( "Question 721688: Jason is driving a boat against the 5 mph current for 3 hours. then, he drives back, which takes 1.5 hours. how fast would he travel in still water? \n" ); document.write( "

Algebra.Com's Answer #442472 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
Let $\"+s+\"$ = the speed of the boat in still water in mi/hr
\n" ); document.write( " $\"+s+%2B+5+\"$ = his speed going with the current in mi/hr
\n" ); document.write( " $\"+s+-+5+\"$ = his speed going against the current in mi/hr
\n" ); document.write( "---------------
\n" ); document.write( "Against the current:
\n" ); document.write( " $\"+d+=+%28+s+-+5+%29%2A3+\"$
\n" ); document.write( " $\"+d+=+%28+s+%2B+5+%29%2A1.5+\"$
\n" ); document.write( "-------------------
\n" ); document.write( "By substitution:
\n" ); document.write( " $\"+%28+s+-+5+%29%2A3+=+%28+s+%2B+5+%29%2A1.5+\"$
\n" ); document.write( " $\"+3s+-+15+=+1.5s+%2B+7.5+\"$
\n" ); document.write( " $\"+1.5s+=+22.5+\"$
\n" ); document.write( " $\"+s+=+15+\"$
\n" ); document.write( "He would travel 15 mi/hr in still water \n" ); document.write( "

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