document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1068185>Question 1068185</A>: <I><SPAN STYLE=\"word-break: break-all;\"> On a windy day,  a boat traveled 210 km in 15 hours. When travelling against the wind,  it took 21hours for the boat to travel back. What was the rate of the boat in still air and what was the velocity of the wind that hindered the speed of the boat?  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #683405 by </B><A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><B>ankor@dixie-net.com(22740)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><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/cgi-bin/show-face.mpl?user=ankor@dixie-net.com><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=683405\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\">  On a windy day, a boat traveled 210 km in 15 hours.<BR>\n" );
document.write( " When travelling against the wind, it took 21 hours for the boat to travel back.<BR>\n" );
document.write( " What was the rate of the boat in still air and what was the velocity of the wind that hindered the speed of the boat? <BR>\n" );
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document.write( "let s = the normal speed of the boat on a windless day<BR>\n" );
document.write( "let w = the rate of the wind<BR>\n" );
document.write( "then<BR>\n" );
document.write( "(s+w) = the effective speed with the wind<BR>\n" );
document.write( "and<BR>\n" );
document.write( "(s-w) = the effective speed against the wind<BR>\n" );
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document.write( "Write distance equation for each way. dist = time * speed<BR>\n" );
document.write( "15(s+w) = 210<BR>\n" );
document.write( "21(s-w) = 210<BR>\n" );
document.write( "simplify both equations, divide the first by 15, divide the second by 21<BR>\n" );
document.write( "s + w = 14<BR>\n" );
document.write( "s - w = 10<BR>\n" );
document.write( "-------------addition eliminates w find s<BR>\n" );
document.write( "2s + 0 = 24<BR>\n" );
document.write( "s = 24/2<BR>\n" );
document.write( "s = 12 km/h is the speed of the boat<BR>\n" );
document.write( ":<BR>\n" );
document.write( "Find the rate of the wind using the  1st simplified equation<BR>\n" );
document.write( "12 + w = 14<BR>\n" );
document.write( "w = 14 - 12<BR>\n" );
document.write( "w = 2 km/hr is the rate of the wind<BR>\n" );
document.write( ":<BR>\n" );
document.write( ":<BR>\n" );
document.write( "Check this in the statement<BR>\n" );
document.write( "\" On a windy day, a boat traveled 210 km in 15 hours.\"<BR>\n" );
document.write( "15(12 + 2) = <BR>\n" );
document.write( "15(14) = 210 km </SPAN>\n" );
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