document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=783768>Question 783768</A>: <I><SPAN STYLE=\"word-break: break-all;\"> John can mow the lawn in three hours. Henry can mow the lawn in seven hours. If they work together how long will it take to mow the lawn? \r<BR>\n" );
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document.write( "And could you please show the work so it will help me understand.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #476938 by </B><A HREF=/tutors/aboutme.mpl?userid=lwsshak3><B>lwsshak3(11628)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=lwsshak3><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=476938\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> John can mow the lawn in three hours. Henry can mow the lawn in seven hours. If they work together how long will it take to mow the lawn?<BR>\n" );
document.write( "And could you please show the work so it will help me understand. <BR>\n" );
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document.write( "John can mow the lawn by himself in three hours, so, in one hour he can finish 1/3 of the job, his work rate.<BR>\n" );
document.write( "Similarly, Henry can mow the lawn by himself in seven hours, so, in one hour he can finish 1/7 of the job, his work rate.<BR>\n" );
document.write( "John and Henry working together can finish the job in x hours,  so, in one hour they can finish 1/x of the job, their work rate.<BR>\n" );
document.write( "..<BR>\n" );
document.write( "sum of individual work rates=work rate working together<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%2F3%2B1%2F7=1%2Fx ALIGN=MIDDLE  ALT=\"1%2F3%2B1%2F7=1%2Fx\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "LCD=21x<BR>\n" );
document.write( "7x+3x=21<BR>\n" );
document.write( "10x=21<BR>\n" );
document.write( "x=21/10=2.1<BR>\n" );
document.write( "Working together how long will it take to mow the lawn? 2.1 hours<BR>\n" );
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