document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1130533>Question 1130533</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A motorboat traveling a distance of 105 miles in 3 hours while traveling with the current. Against the current, the same trip took 7 hours. Find the rate of the boat in calm water and the rate of the current.<BR>\n" );
document.write( "rate of boat_____mph<BR>\n" );
document.write( "rate of current	     mph<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #747227 by </B><A HREF=/tutors/aboutme.mpl?userid=greenestamps><B>greenestamps(13200)</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=747227\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <br><BR>\n" );
document.write( "Note that you can solve the problem informally, using logical reasoning and some simple calculations, instead of using the formal algebraic approach shown by tutor @ikleyn.  The formal algebraic method is certainly valid; but if you just need to solve the problem quickly by whatever method you want (as in a timed mathematics competition), then this alternative method is very useful.<br><BR>\n" );
document.write( "Simple calculations show that the speed of the boat with the current is 35mph while its speed against the current is 15mph.<br><BR>\n" );
document.write( "The 35mph is the boat's speed PLUS the speed of the current; the 15mph is the boat's speed MINUS the speed of the current.  Common sense then says that the speed of the boat is halfway between 15mph and 35mph: 25mph.  And then the speed of the current is the difference between 25mph and either 15mph or 35mph.<br><BR>\n" );
document.write( "So the speed of the boat is 25mph and the speed of the current is 10mph. </SPAN>\n" );
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