document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=424737>Question 424737</A>: <I><SPAN STYLE=\"word-break: break-all;\"> larry can paint the walls of his apartment in 8h. after he has worked for 3h, patrick joins him , and together they finish the job in 2h. how long would it take patrick to do the entire painting job without larry? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #844367 by </B><A HREF=/tutors/aboutme.mpl?userid=greenestamps><B>greenestamps(13203)</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=844367\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <br><BR>\n" );
document.write( "A formal algebraic solution like the one shown in the response from the other tutor is fine; and probably a formal algebraic solution was wanted.<br><BR>\n" );
document.write( "But you can get good mental exercise (and good problem-solving experience!) by solving the problem informally, using logical reasoning and simple arithmetic.<br><BR>\n" );
document.write( "Larry takes 8 hours to do the job himself, and he worked for 3 hours before Patrick joined him.  So 3/8 of the job is done; 5/8 of it remains to be done.<br><BR>\n" );
document.write( "In the next 2 hours that it takes the two of them to finish the job, Larry does another 2/8 of the job, which means Patrick does 3/8 of the job.<br><BR>\n" );
document.write( "Since Patrick does 3/8 of the job in the time Larry does 2/8, Patrick's rate of work is 3/2 Larry's rate; that means he can complete the whole job alone in 2/3 the time it takes Larry to do the job alone.<br><BR>\n" );
document.write( "2/3 of 8 hours is 16/3 hours, or 5 1/3 hours.<br><BR>\n" );
document.write( "ANSWER: 5 1/3 hours<br><BR>\n" );
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