document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1064251>Question 1064251</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Machine A can do a certain job in 8 hours. machine B can do the same job in 10 hours. machine C can do the same job in 12 hours. all three machines start the job at 9.00 am, machine B breaks down at 11.00am and the other two machines finish the job. approximately at what time would the job be completed?<BR>\n" );
document.write( "(please explain the method)\r<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #679298 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><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=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=679298\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> in one hour<BR>\n" );
document.write( "A does 1/8, B does 1/10, C does 1/12<BR>\n" );
document.write( "x is the number of total hours worked.<BR>\n" );
document.write( "B worked 2 hours<BR>\n" );
document.write( "2/8+2/10+2/12=30/120+24/120+20/120=74/120 of the job done by all three.<BR>\n" );
document.write( "The other two account for 46/120; that comes from the fact that if 74/120 was done by all 3, the remaining 46/120 (74+46=120) were done by the two remaining machines.<BR>\n" );
document.write( "x/8+x/12=46/120<BR>\n" );
document.write( "15x/120+10x/120=46/120<BR>\n" );
document.write( "15x+10x=46<BR>\n" );
document.write( "25x=46<BR>\n" );
document.write( "x=1.84 hours or 12:50.24 ANSWER<BR>\n" );
document.write( "check<BR>\n" );
document.write( "A worked 3.84 hours, B 2 hours and C 3.84 hours<BR>\n" );
document.write( "3.84/8+2/10+3.84/12=<BR>\n" );
document.write( "common denominator=120<BR>\n" );
document.write( "57.6+24+38.4 is the numerator, which adds to 120. </SPAN>\n" );
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