document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=630704>Question 630704</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Christopher can paint the interior of his house in 15 hours. If he hires Cynthia to help him, they can do the same job together in 9 hours. If he lets Cynthia work alone, how long will it take her to paint the interior of his house? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #397167 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=397167\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Christopher can paint the interior of his house in 15 hours.<BR>\n" );
document.write( " If he hires Cynthia to help him, they can do the same job together in 9 hours.<BR>\n" );
document.write( " If he lets Cynthia work alone, how long will it take her to paint the interior of his house?<BR>\n" );
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document.write( "Let c = time required by Cynthia alone<BR>\n" );
document.write( "let the completed job = 1 (a painted house)<BR>\n" );
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document.write( "Each will do a fraction of the job. The two fractions add up to one.<BR>\n" );
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document.write( "A shared work equation<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=9%2F15 ALIGN=MIDDLE  ALT=\"9%2F15\"   DISABLED_style= \"max-width:90%; height:auto;\" > + <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=9%2Fc ALIGN=MIDDLE  ALT=\"9%2Fc\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 1<BR>\n" );
document.write( "Reduce fraction<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=3%2F5 ALIGN=MIDDLE  ALT=\"3%2F5\"   DISABLED_style= \"max-width:90%; height:auto;\" > + <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=9%2Fc ALIGN=MIDDLE  ALT=\"9%2Fc\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 1<BR>\n" );
document.write( "Multiply by 5c, resulting in:<BR>\n" );
document.write( "3c + 5(9) = 5c<BR>\n" );
document.write( "45 = 5c - 3c<BR>\n" );
document.write( "45 = 2c<BR>\n" );
document.write( "c = 45/2<BR>\n" );
document.write( "c = 22.5 hrs, Cynthia alone<BR>\n" );
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document.write( "Check this on a calc<BR>\n" );
document.write( "9/15 + 9/22.5 =<BR>\n" );
document.write( ".6 + .4 = 1 </SPAN>\n" );
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