document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=101019>Question 101019</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Biotech Company is selling their product in single units for $4.17 each and in bulk bundles of 10 which cost $25.85 per bundle.<BR>\n" );
document.write( "They sell 829 units of their product in one day which gives them a gross revenue of $2,426.68.<BR>\n" );
document.write( "How many single units and how many bundles did they sell that day?\r<BR>\n" );
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document.write( "here is what i have so far:\r<BR>\n" );
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document.write( "4.17x + 25.85y = 2426.68<BR>\n" );
document.write( "x + y = 829\r<BR>\n" );
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document.write( "for some reason i can't get the answer to work out. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #73524 by </B><A HREF=/tutors/aboutme.mpl?userid=doukungfoo><B>doukungfoo(195)</B></A><img src=\"/images/stars/stars-09.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=doukungfoo><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=doukungfoo><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=73524\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> your first equation is correct but the second one is wrong<BR>\n" );
document.write( "It should be<BR>\n" );
document.write( "x + 10y = 829\r<BR>\n" );
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document.write( "Reason is because y is equal to bundles of 10.<BR>\n" );
document.write( "So to find out how many single units were sold in all the bundles sold <BR>\n" );
document.write( "you have to multiply number of bundles (y) times 10 (# of single units in each bundle)\r<BR>\n" );
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document.write( "y = number of bundles (bundles contain 10 units)<BR>\n" );
document.write( "x = single unit\r<BR>\n" );
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document.write( "Ok so here are the two equations:<BR>\n" );
document.write( "4.17x + 25.85y = 2426.68<BR>\n" );
document.write( "and<BR>\n" );
document.write( "x + 10y = 829\r<BR>\n" );
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document.write( "Start with the second equation. Set it equal to x<BR>\n" );
document.write( "x = 829 - 10y<BR>\n" );
document.write( "now use this value of x in the first equation so<BR>\n" );
document.write( "4.17(x) + 25.85y = 2426.68<BR>\n" );
document.write( "4.17(829 - 10y) + 25.85y = 2426.68<BR>\n" );
document.write( "3456.93 - 41.7y + 25.85y = 2426.68<BR>\n" );
document.write( "3456.93 - 15.85y = 2426.68<BR>\n" );
document.write( "-15.85y = 2426.68 - 3456.93<BR>\n" );
document.write( "-15.85y = -1030.25<BR>\n" );
document.write( "y = 65<BR>\n" );
document.write( "Ok at this point we have solved for y which is the number of bundles<BR>\n" );
document.write( "So 65 bundles\r<BR>\n" );
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document.write( "Now we can take this value for y and plug it into the second equation to <BR>\n" );
document.write( "find the number of single units sold (x)<BR>\n" );
document.write( "x + 10y = 829<BR>\n" );
document.write( "x + 10(65) = 829<BR>\n" );
document.write( "x + 650 = 829<BR>\n" );
document.write( "x = 179<BR>\n" );
document.write( "So the number of single units sold is 179\r<BR>\n" );
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document.write( "I got 65 bundles and 179 single units sold.<BR>\n" );
document.write( "so<BR>\n" );
document.write( "179 + 10(65) = 829\r<BR>\n" );
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document.write( " </SPAN>\n" );
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