document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=521817>Question 521817</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A Jet Ski rider can travel 16 miles against the current of the lower Mississippi River in 1/2 hour and make the return trip with the current in 1/3 hour. Find the speed of the Jet Ski in still water and the speed of the current.\r<BR>\n" );
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document.write( "mph (jet ski in still water)?<BR>\n" );
document.write( "mph (current)? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #346592 by </B><A HREF=/tutors/aboutme.mpl?userid=oberobic><B>oberobic(2304)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=oberobic><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=346592\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> d = r*t is the basic distance equation:  distance = rate * time<BR>\n" );
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document.write( "d = 16 miles<BR>\n" );
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document.write( "r = j - c when going upstream<BR>\n" );
document.write( "j -c = jetski speed minus current speed<BR>\n" );
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document.write( "r = j+c when going downstream<BR>\n" );
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document.write( "t = 1/2 hr going upstream<BR>\n" );
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document.write( "16 = 1/2*(j-c)<BR>\n" );
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document.write( "t = 1/3 hr going downstream<BR>\n" );
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document.write( "16 = 1/3(j+c)<BR>\n" );
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document.write( "16=16<BR>\n" );
document.write( "so<BR>\n" );
document.write( "1/2*(j-c) = 1/3*(j+c)<BR>\n" );
document.write( "(j-c)/2 = (j+c)/3<BR>\n" );
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document.write( "Cross multiply<BR>\n" );
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document.write( "3(j-c) = 2(j+c)<BR>\n" );
document.write( "3j -3c = 2j + 2c<BR>\n" );
document.write( "j = 5c<BR>\n" );
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document.write( "substitute<BR>\n" );
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document.write( "16 = 1/2*(5c-c)<BR>\n" );
document.write( "32 = 4c<BR>\n" );
document.write( "4c = 32<BR>\n" );
document.write( "c = 8<BR>\n" );
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document.write( "Substitute<BR>\n" );
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document.write( "j = 5c<BR>\n" );
document.write( "j = 40<BR>\n" );
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document.write( "Check distances traveled in the given times to determine if this answer is correct.<BR>\n" );
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document.write( "1/2*(40-8) = 16<BR>\n" );
document.write( "1/3*(40+8) = 16<BR>\n" );
document.write( "Correct.<BR>\n" );
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document.write( "Answer:  The speed of the jetski in still water is 40 mph, and the speed of the current is 8 mph. </SPAN>\n" );
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