document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1200128>Question 1200128</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A small grain combine can harvest 100 acres in 24 hours, a medium combine can do the same job in 18 hours, and a large combine can do the job in 12 hours. If all three combines are used at the same time, how long will it take to harvest 800 acres? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #834160 by </B><A HREF=/tutors/aboutme.mpl?userid=greenestamps><B>greenestamps(13200)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=greenestamps><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=greenestamps><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=834160\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <br><BR>\n" );
document.write( "The response from the other tutor shows a solution using the standard algebraic method, using the work rates of the three combines.<br><BR>\n" );
document.write( "A different method usually makes for a solution using simpler calculations.<br><BR>\n" );
document.write( "Consider the least common multiple of the three given times for harvesting 100 acres: 72 hours.  In 72 hours...<BR>\n" );
document.write( "the small combine can harvest 100*3 = 300 acres;<BR>\n" );
document.write( "the medium combine can harvest 100*4 = 400 acres; and<BR>\n" );
document.write( "the large combine can harvest 100*6 = 600 acres<br><BR>\n" );
document.write( "So in 72 hours the three combines together could harvest 300+400+600 = 1300 acres; that means the time to harvest 800 acres is<br><BR>\n" );
document.write( "ANSWER: (8/13)*72 hours = 576/13 hours or about 44.3 minutes.<br><BR>\n" );
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