document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1171616>Question 1171616</A>: <I><SPAN STYLE=\"word-break: break-all;\">  Paddlewheel Pat has a motorboat.  He can travel a distance of 10 miles boating into the current in the same time it takes him to travel 15 miles with the current.  If the current has a speed of 3 mph, what is the speed of Pat’s boat in still water? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #796570 by </B><A HREF=/tutors/aboutme.mpl?userid=greenestamps><B>greenestamps(13209)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=greenestamps><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=greenestamps><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=796570\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <br><BR>\n" );
document.write( "Here is a highly unusual way for solving this kind of problem that I personally find easy to use.<br><BR>\n" );
document.write( "Take a look at it and see if it \"works\" for you.  If not, there are of course many other ways to solve the problem.<br><BR>\n" );
document.write( "The times are the same, and the distances are in the ratio 10:15 = 2:3.  That means the speeds are in the ratio 2:3.<br><BR>\n" );
document.write( "If the speed of the boat in still water is x, then the upstream speed is x-3 and the downstream speed is x+3.<br><BR>\n" );
document.write( "Solve for x by writing the ratio 2:3 as an equivalent ratio in which the difference between the two numbers is the difference between the upstream and downstream speeds:<br><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2%2F3+=+%28x-3%29%2F%28x%2B3%29 ALIGN=MIDDLE  ALT=\"2%2F3+=+%28x-3%29%2F%28x%2B3%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
document.write( "On the left, the difference between numerator and denominator is 1; on the right is is 6.  To get the desired equivalent ratio, multiply numerator and denominator on the left by 6.<br><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2%2F3+=+12%2F18+=+%28x-3%29%2F%28x%2B3%29 ALIGN=MIDDLE  ALT=\"2%2F3+=+12%2F18+=+%28x-3%29%2F%28x%2B3%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
document.write( "So x-3 is 12 and x+3 is 18; that means x is 15.<br><BR>\n" );
document.write( "ANSWER: The speed of the boat in still water is 15 mph.<br><BR>\n" );
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