document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=734088>Question 734088</A>: <I><SPAN STYLE=\"word-break: break-all;\"> \r<BR>\n" );
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document.write( "A teacher bought 20 books in a sale. Some cost £8 each and the others cost £3<BR>\n" );
document.write( "each. She spent £110 in all. How many of the £3 books did she buy? Let x be<BR>\n" );
document.write( "the number of £3 books she bought </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #448719 by </B><A HREF=/tutors/aboutme.mpl?userid=checkley79><B>checkley79(3341)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=checkley79><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=448719\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> X+Y=20<BR>\n" );
document.write( "X=20-Y<BR>\n" );
document.write( "3X+8Y=110<BR>\n" );
document.write( "3(20-Y)+8Y=110<BR>\n" );
document.write( "60-3Y+8Y=110<BR>\n" );
document.write( "5Y=110-60<BR>\n" );
document.write( "5Y=50<BR>\n" );
document.write( "Y=50/5<BR>\n" );
document.write( "Y=10 NUMBER OF 8 DOLLAR(?) BOOKS.<BR>\n" );
document.write( "X=20-10=10 NUMBER OF 3 DOLLAR (?) BOOKS.<BR>\n" );
document.write( "PROOF:<BR>\n" );
document.write( "3*10+8*10=110<BR>\n" );
document.write( "30+80=110<BR>\n" );
document.write( "110=110 </SPAN>\n" );
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