document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=83319>Question 83319</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/0618203230/algebrahomeworkh>introductory algebra</A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> Sam can mow the lawn in 20 minutes. Bob can mow the lawn in 30 minutes. if they work together, how long will it take to completely mow the lawn? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #59836 by </B><A HREF=/tutors/aboutme.mpl?userid=vertciel><B>vertciel(183)</B></A><img src=\"/images/stars/stars-09.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=vertciel><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=59836\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The idea behind this problem is simple: one adds the rates of work.\r<BR>\n" );
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document.write( "However, you cannot add 20 and 30 minutes because they are not proportional, so we will make them proportionate.\r<BR>\n" );
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document.write( "If Sam mows the lawn in 20 minutes, he mows 1/20 of the lawn in 1 minute.\r<BR>\n" );
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document.write( "Likewise, Bob mows 1/30 of the lawn in 1 minute.\r<BR>\n" );
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document.write( "Now since the rates (ratios) of work are proportional to 1 minute, you can add them to find the time needed by both of them working together. </SPAN>\n" );
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