document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1203109>Question 1203109</A>: <I><SPAN STYLE=\"word-break: break-all;\"> It took a patrol boat 5 hours to travel 60 km up a river against the current, and 3 hours for the return trip with the current. Find the speed of the boat in still water and the speed of the current. </SPAN>\n" );
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document.write( "b = speed of boat in still water<BR>\n" );
document.write( "c = speed of the current<BR>\n" );
document.write( "speeds are in kilometers per hour (kph or km/hr)\r<BR>\n" );
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document.write( "When going upstream against the current, the boat's speed b drops to b-c.\r<BR>\n" );
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document.write( "distance = rate*time<BR>\n" );
document.write( "d = r*t<BR>\n" );
document.write( "60 = (b-c)*5<BR>\n" );
document.write( "60/5 = b-c <BR>\n" );
document.write( "12 = b-c<BR>\n" );
document.write( "12+c = b<BR>\n" );
document.write( "b = c+12\r<BR>\n" );
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document.write( "The boat's speed in still water is found by adding 12 to the current's speed.\r<BR>\n" );
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document.write( "When going downstream, the current speeds the boat up to b+c kph.\r<BR>\n" );
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document.write( "distance = rate*time<BR>\n" );
document.write( "d = r*t<BR>\n" );
document.write( "60 = (b+c)*3<BR>\n" );
document.write( "60/3 = b+c<BR>\n" );
document.write( "20 = b+c<BR>\n" );
document.write( "20 = c+12+c ...... replace b with c+12<BR>\n" );
document.write( "20 = 2c+12<BR>\n" );
document.write( "2c+12 = 20<BR>\n" );
document.write( "2c = 20-12<BR>\n" );
document.write( "2c = 8<BR>\n" );
document.write( "c = 8/2<BR>\n" );
document.write( "c = 4<BR>\n" );
document.write( "The current has a speed of 4 km/hr.\r<BR>\n" );
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document.write( "The boat's speed is 16 kph because of this scratch work<BR>\n" );
document.write( "b = c+12<BR>\n" );
document.write( "b = 4+12<BR>\n" );
document.write( "b = 16\r<BR>\n" );
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document.write( "Answers:<BR>\n" );
document.write( "Speed of boat in still water = <font size=4 color=red>16 km per hr</font> <BR>\n" );
document.write( "Speed of current = <font size=4 color=red>4 km per hr</font> <BR>\n" );
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