document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=578104>Question 578104</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Tom and Jerry have a mowing business. It takes Tom 30 minutes to mow a yard and it takes Jerry 40 minutes to mow the same yard. If they work together, how long will it takes them to mow the yard?\r<BR>\n" );
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document.write( "I was thinking along the lines of Average rate between them is 35 minutes and if both of them are mowing it will be half of that which is 17.5 minutes. \r<BR>\n" );
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document.write( "The answer in the back of the book states that it will take 120/7 minutes. I have no idea how they got these figures? Any assistance would be appreciated.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #370511 by </B><A HREF=/tutors/aboutme.mpl?userid=josmiceli><B>josmiceli(19441)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josmiceli><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=josmiceli><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=370511\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Add their rates of working to get<BR>\n" );
document.write( " rate of working together<BR>\n" );
document.write( "Tom's rate: ( 1 yard ) / ( 30 min )<BR>\n" );
document.write( "Jerry's rate: ( 1 yard ) / ( 40 min )<BR>\n" );
document.write( "Let <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+t+ ALIGN=MIDDLE  ALT=\"+t+\"   DISABLED_style= \"max-width:90%; height:auto;\" > = time in minutes to mow yard working together<BR>\n" );
document.write( "Their rate working together: ( 1 yard ) / ( t min )<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+1%2F30+%2B+1%2F40+=+1%2Ft+ ALIGN=MIDDLE  ALT=\"+1%2F30+%2B+1%2F40+=+1%2Ft+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Multiply both sids by <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+120t+ ALIGN=MIDDLE  ALT=\"+120t+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+4t+%2B+3t+=+120+ ALIGN=MIDDLE  ALT=\"+4t+%2B+3t+=+120+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+7t+=+120+ ALIGN=MIDDLE  ALT=\"+7t+=+120+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+t+=+120%2F7+ ALIGN=MIDDLE  ALT=\"+t+=+120%2F7+\"   DISABLED_style= \"max-width:90%; height:auto;\" > min<BR>\n" );
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document.write( "All these type of problems are about adding ( sometimes subtracting ) rates </SPAN>\n" );
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