document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=906229>Question 906229</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A Web music store offers two versions of a popular song. The size of the standard version is 2.9 megabytes (MB). The size of the high-quality version is 4.4 MB. Yesterday, there were 1010 downloads of the song, for a total download size of 3424 MB. How many downloads of the high-quality version were there?\r<BR>\n" );
document.write( "\n" );
document.write( "*Really need help on this problem. Tried it several times and could not get the answer. Please help. Thanks! :) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #549670 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=549670\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> let x = number of standard quality downloads at 2.9 MB.<BR>\n" );
document.write( "let y = number of high quality downloads at 4.4 MB.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "x + y = 1010<BR>\n" );
document.write( "2.9x + 4.4y = 3424\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "these 2 equations need to be solved simultaneously either by graphing or by substitution or by elimination or by matrix methods which are similar to elimination.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "we'll do elimination.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "mjultiply both sides of the first equation by 2.9 to get:\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "2.9x + 2.9y = 2929<BR>\n" );
document.write( "2.9x + 4.4y = 3424\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "subtract the first equation from the second eqution to get:\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "1.5y = 495\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "divide both sides by 1.5 to get y = 330\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "since x + y = 1010, this means that x has to be equal to 680 because 680 + 330 = 1010.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "since you used the first equation to solve for x, then use the second equation to confirm your solutions are correct by replacing x with 680 and y with 330 in that equation to get:\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "2.9x + 4.4y = 3424 becomes 2.9*680 + 4.4*330 = 3424 which becomes 1972 + 1452 = 3424 which becomes 3424 = 3424, confirming your solution is correct.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "your solution is:\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "number of high quality downloads was 330.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );