document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1165824>Question 1165824</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Mark, Lex, and Bren can finish a job 12,16, and 19 hours, respectively. Mark and Lex worked together for 4 hours. Lex got tired so Bren worked in place of him until the job is finished. How long did Mark work? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #790327 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=790327\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> in one hour, Mark does 1/12, Lex 1/16, and Bren 1/19 of the job<BR>\n" );
document.write( "In 4 hours, Mark did 4/12, Lex 4/16<BR>\n" );
document.write( "That is 1/3 + 1/4 of the job or 7/12<BR>\n" );
document.write( "Mark needs to work x more hours to do x/12, and Bren x hours to do x/19<BR>\n" );
document.write( "that sum is 5/12<BR>\n" );
document.write( "(x/12)+(x/19)=5/12<BR>\n" );
document.write( "multiply by 228,<BR>\n" );
document.write( "19x+12x=95<BR>\n" );
document.write( "31x=95<BR>\n" );
document.write( "x=3.06 hours\r<BR>\n" );
document.write( "\n" );
document.write( "so Mark worked 7.06 hours and did 58.8% of the job<BR>\n" );
document.write( "Lex worked 4 hours and did 25% of the job<BR>\n" );
document.write( "Bren worked 3.06 hours and did 3.06/19 or 16.1% of the job <BR>\n" );
document.write( "Within rounding error, this is the 100% </SPAN>\n" );
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