document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1152573>Question 1152573</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Four workers are building a house. In five days they built half the house. But<BR>\n" );
document.write( "winter is coming and they want to finish building the house in two more days.<BR>\n" );
document.write( "How many friends should the workers call for help, if they do not want to bother<BR>\n" );
document.write( "more people than is necessary?  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #774621 by </B><A HREF=/tutors/aboutme.mpl?userid=greenestamps><B>greenestamps(13200)</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=774621\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <br><BR>\n" );
document.write( "There are of course many different ways to solve the problem.  The solution from the other tutor uses formal mathematics, which is fine.<br><BR>\n" );
document.write( "I prefer a less formal solution using common sense, like this:<br><BR>\n" );
document.write( "Half the house was built by 4 workers in 5 days.  So 20 man-days builds half of a house.<br><BR>\n" );
document.write( "The other half remains to be built; it will require another 20 man-days.<br><BR>\n" );
document.write( "They want to finish in 2 days; the number of workers required is 20/2 = 10.<br><BR>\n" );
document.write( "There are currently 4 workers; the number of additional workers required is 10-4=6.<br><BR>\n" );
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