document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1121174>Question 1121174</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A and B working together can complete a job in 30 days. After they had both worked 18 days, however, A left and B finished the work in 20 more days. Find the time in which each can do the work alone.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #736939 by </B><A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><B>ankor@dixie-net.com(22740)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><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=ankor@dixie-net.com><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=736939\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A and B working together can complete a job in 30 days.<BR>\n" );
document.write( " After they had both worked 18 days, however, A left and B finished the work in 20 more days.<BR>\n" );
document.write( " Find the time in which each can do the work alone.<BR>\n" );
document.write( ":<BR>\n" );
document.write( "let a = time A required to complete the job alone<BR>\n" );
document.write( "let b = time for B alone<BR>\n" );
document.write( "let the completed job = 1<BR>\n" );
document.write( ":<BR>\n" );
document.write( "Write an equation for each statement<BR>\n" );
document.write( "\"A and B working together can complete a job in 30 days.\"<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=30%2Fa ALIGN=MIDDLE  ALT=\"30%2Fa\"   DISABLED_style= \"max-width:90%; height:auto;\" > + <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=30%2Fb ALIGN=MIDDLE  ALT=\"30%2Fb\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 1<BR>\n" );
document.write( "multiply eq by ab<BR>\n" );
document.write( "30b + 30a = ab<BR>\n" );
document.write( "\"After they had both worked 18 days, however, A left and B finished the work in 20 more days.\"<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=18%2Fa ALIGN=MIDDLE  ALT=\"18%2Fa\"   DISABLED_style= \"max-width:90%; height:auto;\" > + <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=38%2Fb ALIGN=MIDDLE  ALT=\"38%2Fb\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 1<BR>\n" );
document.write( "18b + 38a = ab<BR>\n" );
document.write( ":<BR>\n" );
document.write( "ab = ab therfore<BR>\n" );
document.write( "18b + 38a = 30b + 30a<BR>\n" );
document.write( "38a - 30a = 30b - 18b<BR>\n" );
document.write( "8a = 12b<BR>\n" );
document.write( "a = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=12%2F8 ALIGN=MIDDLE  ALT=\"12%2F8\"   DISABLED_style= \"max-width:90%; height:auto;\" >b<BR>\n" );
document.write( "a = 1.5b<BR>\n" );
document.write( ":<BR>\n" );
document.write( "Using the first equation, replace a with 1.5b<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=30%2F%281.5b%29 ALIGN=MIDDLE  ALT=\"30%2F%281.5b%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > + <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=30%2Fb ALIGN=MIDDLE  ALT=\"30%2Fb\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 1<BR>\n" );
document.write( "multiply by b<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=30%2F1.5 ALIGN=MIDDLE  ALT=\"30%2F1.5\"   DISABLED_style= \"max-width:90%; height:auto;\" > + 30 = b<BR>\n" );
document.write( "20 + 30 = b<BR>\n" );
document.write( "b = 50 hrs B working alone<BR>\n" );
document.write( "then find a<BR>\n" );
document.write( "1.5(50) = 75 hrs b working alone<BR>\n" );
document.write( "   </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );