document.write( "Question 29338: The speed of a boat in still water is 16 mph. The boat traveled the same distance downstream in 9 minutes that it traveled upstream in 15 minutes. Find the speed of the current....HELP! \n" ); document.write( "
Algebra.Com's Answer #16132 by josmiceli(19441)\"\" \"About 
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c = speed of current in miles/hr
\n" ); document.write( "16 = speed of boat in still water (given) in miles/hr
\n" ); document.write( "d = distance travelled in miles
\n" ); document.write( "t[1] = time travelling upstream
\n" ); document.write( "t[2] = time travelling downstream
\n" ); document.write( "16 + c = speed of boat going with current in miles/hr
\n" ); document.write( "16 - c = speed of boat against current in miles/hr
\n" ); document.write( "d[1] = (rate upstream)x(time upstream)
\n" ); document.write( "d[2] = (rate downstream)x(time downstream)
\n" ); document.write( "d[1] = d[2] (given)
\n" ); document.write( "(16 + c)mi/hr x 9 min x 1 hr/60 min = (16 - c) x 15 min x 1 hr/60 min
\n" ); document.write( "notice that (mi/hr)(min)(hr/min) = mi as it should
\n" ); document.write( "(16 + c)(9/60) = (16 - c)(15/60)
\n" ); document.write( "multiply both sides by 60/3
\n" ); document.write( "(16 + c) x 3 = (16 - c) x 5
\n" ); document.write( "48 + 3c = 80 - 5c
\n" ); document.write( "8c = 32
\n" ); document.write( "c = 4 mi/hr answer
\n" ); document.write( "check
\n" ); document.write( "(16 + 4) x 3 = (16 - 4) x 5
\n" ); document.write( "20 x 3 = 12 x 5
\n" ); document.write( "60 = 60
\n" ); document.write( "checks \n" ); document.write( "
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