document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=347014>Question 347014</A>: <I><SPAN STYLE=\"word-break: break-all;\"> It takes a boy 90 minutes to mow the lawn, but his sister can mow it in 60 minutes. How long would it take them to mow the lawn if they worked together, using two lawn mowers? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #248157 by </B><A HREF=/tutors/aboutme.mpl?userid=ptaylor><B>ptaylor(2198)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ptaylor><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=ptaylor><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=248157\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Let x=time required to mow the lawn if both work together<BR>\n" );
document.write( "Then both work at the rate of 1/x lawn per min<BR>\n" );
document.write( "boy works at the rate of 1/90 lawn per min<BR>\n" );
document.write( "sis works at the rate of 1/60 lawn per min<BR>\n" );
document.write( "Then both work at the rate of 1/90 + 1/60=2/180+3/180=5/180=1/36 lawn per min<BR>\n" );
document.write( "So our equation to solve is<BR>\n" );
document.write( "1/36=1/x  multiply each side by 36x<BR>\n" );
document.write( "x=36 min----time it takes both working together\r<BR>\n" );
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document.write( "CK<BR>\n" );
document.write( "in 36 min boy mows (1/90)*36=36/90=6/15 of the lawn<BR>\n" );
document.write( "in 36 min girl mows (1/60)*36 =36/60 =9/15 of the lawn\r<BR>\n" );
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document.write( "6/15 + 9/15=15/15=1 (lawn that is)<BR>\n" );
document.write( "Hope this helps---ptaylor </SPAN>\n" );
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