document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=312382>Question 312382</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The number of books N to be sold at a bookfare is given by the function \r<BR>\n" );
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document.write( "N(p) = 25000 / (3p + k)\r<BR>\n" );
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document.write( "where p is the price per book and k is a constant. If 1000 books are sold at $7 per book, how many books will be sold at the price of $10 per book? <BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #223346 by </B><A HREF=/tutors/aboutme.mpl?userid=nerdybill><B>nerdybill(7384)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=nerdybill><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=nerdybill><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=223346\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The number of books N to be sold at a bookfare is given by the function <BR>\n" );
document.write( "N(p) = 25000 / (3p + k) <BR>\n" );
document.write( "where p is the price per book and k is a constant. If 1000 books are sold at $7 per book, how many books will be sold at the price of $10 per book? <BR>\n" );
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document.write( "First, use: \"1000 books are sold at $7 per book\" to find k:<BR>\n" );
document.write( "N(p) = 25000 / (3p + k) <BR>\n" );
document.write( "1000 = 25000 / (3(7) + k) <BR>\n" );
document.write( "1000 = 25000 / (21 + k) <BR>\n" );
document.write( "1000(21 + k) = 25000 <BR>\n" );
document.write( "21000 + 1000k = 25000 <BR>\n" );
document.write( "1000k = 4000 <BR>\n" );
document.write( "k = 4<BR>\n" );
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document.write( "Our formula is now:<BR>\n" );
document.write( "N(p) = 25000 / (3p + 4) <BR>\n" );
document.write( "Now we can answer: \"how many books will be sold at the price of $10 per book?\"<BR>\n" );
document.write( "N(p) = 25000 / (3(10) + 4) <BR>\n" );
document.write( "N(p) = 25000 / (30 + 4) <BR>\n" );
document.write( "N(p) = 25000/34 <BR>\n" );
document.write( "N(p) = 735.29<BR>\n" );
document.write( "But, since we can't sell a partial book:<BR>\n" );
document.write( "N(p) = 735\r<BR>\n" );
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