document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=37839>Question 37839</A>: <I><SPAN STYLE=\"word-break: break-all;\"> 20 men can do a piece of work in 24 days. After working for few days,4 men are added and the work was finished 3 daysearlier.After how many days were 4 men added? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #23360 by </B><A HREF=/tutors/aboutme.mpl?userid=fractalier><B>fractalier(6550)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=fractalier><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=fractalier><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=23360\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Cool problem.<BR>\n" );
document.write( "We know the entire job takes 20 men 24 days to finish, or 480 man-days.<BR>\n" );
document.write( "Now if we let the time they work initially to be t, we know that they worked 20t man-days.  Then after the 4 men are added, they work for an additional 21 - t days, because we are told they take three days less than the original 24 days.<BR>\n" );
document.write( "Okay, now if we add the two parts together, we know they must add up to the original 480 man-days...<BR>\n" );
document.write( "20t + 24(21 - t) = 480<BR>\n" );
document.write( "20t + 504 - 24t = 480<BR>\n" );
document.write( "-4t + 504 - 480<BR>\n" );
document.write( "-4t = -24<BR>\n" );
document.write( "t = 6<BR>\n" );
document.write( "Thus the 4 men were added after 6 days.<BR>\n" );
document.write( "Good problem.  I may steal that one for my students. </SPAN>\n" );
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