document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=708632>Question 708632</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Gertrude and Bertha are sisters. They are responsible for keeping the family's driveway clear of snow. If they work together they can complete shoveling in 30 minutes. One day Gertrude had to do the job alone. It took her 40 minutes. How long would it have taken Bertha to shovel the same amount alone? You can assume that each girl always shovels at a constant speed.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #436180 by </B><A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><B>josgarithmetic(39617)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><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=436180\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> r for rate<BR>\n" );
document.write( "t for time in minutes<BR>\n" );
document.write( "1 job is \"shoveling the snow off the driveway\".\r<BR>\n" );
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document.write( "Shoveler___________rate_________time____________jobs<BR>\n" );
document.write( "Bertha______________r<BR>\n" );
document.write( "Gertrude__________1/40<BR>\n" );
document.write( "Both______________1/30\r<BR>\n" );
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document.write( "Usually one would try to fill in this whole table, but seeing enough information for expressions for rates, and knowing that their rates are additive, we have enough as shown.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=r%2B1%2F40=1%2F30 ALIGN=MIDDLE  ALT=\"r%2B1%2F40=1%2F30\"   DISABLED_style= \"max-width:90%; height:auto;\" >, find r, Bertha's rate. </SPAN>\n" );
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