document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=188529>Question 188529</A>: <I><SPAN STYLE=\"word-break: break-all;\">  A boat took one hour and 50 minutes to go 55km downstream and 3 hours, 40 minutes to return. Find the boat's rate in still water and the rate of the current \r<BR>\n" );
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document.write( "answer: the rate of the boat in still water is 22 1/2 mph; the rate of the current is 7 1/2 mph.\r<BR>\n" );
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document.write( "need a full break down of how my text book got this answer  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #141356 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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=141356\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A boat took one hour and 50 minutes to go 55km downstream and 3 hours, 40 minutes to return. Find the boat's rate in still water and the rate of the current <BR>\n" );
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document.write( "1 hr = 6/6 hr ; 50 minutes = 5/6 hr ; So 1 hr 50 = 11/6 hr<BR>\n" );
document.write( "3 hrs = 9/3 hr ; 40 minutes = 2/3 hr ; So 3 hr 40 min = 11/3 hr<BR>\n" );
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document.write( "Downstream DATA:<BR>\n" );
document.write( "distance = 55 km ; time = (11/6) hr. ; rate = d/t = 55/(11/6) = 30 kph<BR>\n" );
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document.write( "Upstream DATA:<BR>\n" );
document.write( "distance = 55 km ; time = (11/3) hr. ; rate = d/t = 55/(11/3) = 15 kph<BR>\n" );
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document.write( "Equations:<BR>\n" );
document.write( "b + c = 30 kph<BR>\n" );
document.write( "b - c = 15 kph<BR>\n" );
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document.write( "Add to solve for \"b\":<BR>\n" );
document.write( "2b = 45 kph<BR>\n" );
document.write( "b = 22.5 kph (speed of the boat in still water)<BR>\n" );
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document.write( "Substitute to solve for \"c\":<BR>\n" );
document.write( "22.5 + c = 30<BR>\n" );
document.write( "c = 30-22.5 = 7.5 kph ( speed of the current)<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "San H.  </SPAN>\n" );
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