document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=148046>Question 148046</A>: <I><SPAN STYLE=\"word-break: break-all;\"> It takes Johnny 4 hours to mow the lawn. It takes Rebecca 3 hours to mow the same lawn. How long would it take if they worked together?\r<BR>\n" );
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document.write( "I cannot figure out the formula to use to determine this. I keep trying to make 4 and 3 hours equal 1 (lawn). Just not sure where to begin. If I had the formula... thank-you.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #108423 by </B><A HREF=/tutors/aboutme.mpl?userid=edjones><B>edjones(8007)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=edjones><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=edjones><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=108423\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Johnny can do 1/4 the job in 1 hr.<BR>\n" );
document.write( "Rebbecca can do 1/3 the job in 1 hr.<BR>\n" );
document.write( "1/4 + 1/3 <BR>\n" );
document.write( "=(3+4)/12<BR>\n" );
document.write( "=7/12 of the job in 1 hr together.<BR>\n" );
document.write( "12/7 hr. Time it takes both of them to do the job.<BR>\n" );
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document.write( "Ed<BR>\n" );
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