document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=715024>Question 715024</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Black pencil cost#15 each and colored pencil cost #21 each if24 mixed pencil costcost #402 how many of them were black </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #439164 by </B><A HREF=/tutors/aboutme.mpl?userid=JBarnum><B>JBarnum(2146)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=JBarnum><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=JBarnum><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=439164\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> b=black<BR>\n" );
document.write( "c=colored<BR>\n" );
document.write( "b+c=24<BR>\n" );
document.write( "15b+21c=402<BR>\n" );
document.write( "Use substitution<BR>\n" );
document.write( "b=24-c<BR>\n" );
document.write( "15(24-c)+21c=402<BR>\n" );
document.write( "360-15c+21c=402<BR>\n" );
document.write( "360+6c=402<BR>\n" );
document.write( "6c=42<BR>\n" );
document.write( "c=7<BR>\n" );
document.write( "b=24-7<BR>\n" );
document.write( "b=17<BR>\n" );
document.write( "17 black pencils </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );