document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=919280>Question 919280</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Three brothers,Michael,Matthew and Mark are tasked to mow a 2000 square meter garden. In 8 hours, Michael, the eldest, can mow 1200 square meters. Matthew can mow 600 square and Mark, the youngest ca mow 200 square meters. If they work together for 5 hours, what part of the garden is not mowed? \r<BR>\n" );
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document.write( "Follow up question: with reference to the question above, suppose the three brothers worked together for 4 hours but Mark got tired and quit. Matthew stayed for another half-hour and quit. How long will it take Michael to finish the job?  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #557634 by </B><A HREF=/tutors/aboutme.mpl?userid=Theo><B>Theo(13342)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Theo><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=Theo><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=557634\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> lawn to be mowed is 2000 square meters.\r<BR>\n" );
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document.write( "michael can mow 1200 square meters in 8 hours.<BR>\n" );
document.write( "his rate of mowing is therefore 1200 / 8 = 150 square meters per hour.\r<BR>\n" );
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document.write( "matthew can mow 600 square meters in 8 hours.<BR>\n" );
document.write( "his rate of mowing is therefore = 600 / 8 = 75 square meters per hour.\r<BR>\n" );
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document.write( "mark can mow 200 square meters in 8 hours.<BR>\n" );
document.write( "his rate of mowing is therefore = 200 / 8 = 25 square meters per hour.\r<BR>\n" );
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document.write( "when they work together, their rates are additive.\r<BR>\n" );
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document.write( "since rate * time = quantity, then you get:\r<BR>\n" );
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document.write( "(150 + 75 + 25) * time = 2000 square meters.\r<BR>\n" );
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document.write( "simplify by combining like terms to get:\r<BR>\n" );
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document.write( "250 * time = 2000 square meters.\r<BR>\n" );
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document.write( "divide both sides of the equation by 250 to get time = 2000 / 250 = 8 hours.\r<BR>\n" );
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document.write( "working together, they will be able to mow the the whole lawn in 8 hours.\r<BR>\n" );
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document.write( "in 5 hours, they will be able to mow 5/8 * 2000 = 1250 square meters.\r<BR>\n" );
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document.write( "looked at another way, their combined rate is 250 square meters per hour.\r<BR>\n" );
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document.write( "multiply that by 5 and you get 5 * 250 = 1250 square meters.\r<BR>\n" );
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document.write( "since the lawn is 2000 square meters and they mow 1250 square meters in 5 hours, then what is left ot mow is 750 square meters.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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