document.write( "Question 234233: #2 A CRUISE BOAT TRAVELS 96 MILES DOWNSTREAM IN 4 HOURS AND RETURNS TO ITS STARTING POINT UPSTREAM IN 12 HOURS. FIND THE SPEED OF THE STREAM.\r
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Algebra.Com's Answer #172978 by ankor@dixie-net.com(22740)\"\" \"About 
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A CRUISE BOAT TRAVELS 96 MILES DOWNSTREAM IN 4 HOURS AND RETURNS TO ITS STARTING POINT UPSTREAM IN 12 HOURS. FIND THE SPEED OF THE STREAM.
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\n" ); document.write( "Let s = speed of the boat in still water
\n" ); document.write( "Let c = speed of the stream
\n" ); document.write( "then
\n" ); document.write( "(s+c) = speed downstream
\n" ); document.write( "(s-c) = speed upstream
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\n" ); document.write( "Write a distance equation for each trip; dist = time * speed
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\n" ); document.write( "4(s +c) = 96
\n" ); document.write( "12(s-c) = 96
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\n" ); document.write( "Simplify, divide the 1st equation by 4 and the 2nd equation by 12
\n" ); document.write( "s + c = 24
\n" ); document.write( "s - c = 8
\n" ); document.write( "-------------subtraction eliminates s, find c:
\n" ); document.write( "2c = 16
\n" ); document.write( "c = 8 mph, speed of the stream, (which is what they asked for)
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\n" ); document.write( "To check solution find the speed of the boat
\n" ); document.write( "s - 8 = 8
\n" ); document.write( "s = 16 mph, speed of the boat
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\n" ); document.write( "Check in both equations
\n" ); document.write( "4(16+8) = 96
\n" ); document.write( "12(16-8) = 96 \n" ); document.write( "
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