document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1206419>Question 1206419</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The ratio of the price of a cassette to the price of a VCD was 1:5. Each VCD cost $25. On a certain day, the amount of money collected from the sale of both VCDs and cassettes was $6720. If the number of cassettes sold made up 1/5 of the total number of VCDs and cassettes sold, how many VCDs were sold on that day? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #843880 by </B><A HREF=/tutors/aboutme.mpl?userid=Theo><B>Theo(13342)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Theo><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=Theo><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=843880\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> c = number of cassettes<BR>\n" );
document.write( "v = number of vcds\r<BR>\n" );
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document.write( "ratio of the price of a cassette to the price of a vcd = 1:5.<BR>\n" );
document.write( "price of a vcd = 25<BR>\n" );
document.write( "price of a cassette = 1/5 * 25 = 5.\r<BR>\n" );
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document.write( "you have two equations that need to be solved simultaneously.\r<BR>\n" );
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document.write( "they are c + v = yet to be determined<BR>\n" );
document.write( "5 * c + 25 * v = 6720\r<BR>\n" );
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document.write( "you are given that c = 1/5 * (c + v)<BR>\n" );
document.write( "that means that v = 4/5 * (c + v))\r<BR>\n" );
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document.write( "in the equation of 5 * c + 25 * v = 6720, replace c with 1/5 * (c + v) and replace v with 4/5 * (c + v) to get:\r<BR>\n" );
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document.write( "1/5 * (c + v) * 5 + 4/5 * (c + v) * 25 = 6720\r<BR>\n" );
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document.write( "factor out the (c + v) to get:\r<BR>\n" );
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document.write( "(c + v) * (1/5 * 5 + 4/5 * 25) = 6720\r<BR>\n" );
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document.write( "simplify to get (c + v) * 21 = 6720\r<BR>\n" );
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document.write( "solve for (c + v) to get (c + v) = 6720 / 21 = 320.\r<BR>\n" );
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document.write( "c = 1/5 * 320 = 64<BR>\n" );
document.write( "v = 4/5 * 320 = 256\r<BR>\n" );
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document.write( "your total price equation becomes 64 * 5 + 256 * 25 = 6720 which becomes 6720 = 6720 which is true.\r<BR>\n" );
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document.write( "your solution is that 256 vcds were sold on that day.\r<BR>\n" );
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document.write( "64 cassettes were sold for 64 * 5 = 320<BR>\n" );
document.write( "256 vcds were sold for 256 * 25 = 6400<BR>\n" );
document.write( "total revenue for the day was 320 + 6400 = 6720.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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