document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1040425>Question 1040425</A>: <I><SPAN STYLE=\"word-break: break-all;\"> QUESTION 2:<BR>\n" );
document.write( "A gas station sells three types of gas: Regular for $2.85 a gallon, Performance Plus for $3.10 a gallon, and Premium for $3.35 a gallon. <BR>\n" );
document.write( "On a particular day 4000 gallons of gas were sold for a total of $12,125. Two times as many gallons of Regular as Premium gas were sold. How many gallons of each type of gas were sold that day?<BR>\n" );
document.write( "I came up with the following system:<BR>\n" );
document.write( "x+y+z=4000<BR>\n" );
document.write( "2.85x+3.10y+3.35z=12125<BR>\n" );
document.write( "x=2x<BR>\n" );
document.write( "I tried using matrices but the answers I get do not work when plugged back into the system. These problems confuse the heck out of me!\r<BR>\n" );
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document.write( "THANK YOU!!!!!! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #655247 by </B><A HREF=/tutors/aboutme.mpl?userid=ikleyn><B>ikleyn(52800)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ikleyn><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=ikleyn><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=655247\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> .<BR>\n" );
document.write( "QUESTION 2:<BR>\n" );
document.write( "A gas station sells three types of gas: Regular for $2.85 a gallon, Performance Plus for $3.10 a gallon, and Premium for $3.35 a gallon. <BR>\n" );
document.write( "On a particular day 4000 gallons of gas were sold for a total of $12,125. <BR>\n" );
document.write( "Two times as many gallons of Regular as Premium gas were sold. How many gallons of each type of gas were sold that day?<BR>\n" );
document.write( "I came up with the following system:<BR>\n" );
document.write( "x+y+z=4000<BR>\n" );
document.write( "2.85x+3.10y+3.35z=12125<BR>\n" );
document.write( "x=2x<BR>\n" );
document.write( "I tried using matrices but the answers I get do not work when plugged back into the system. These problems confuse the heck out of me!\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "THANK YOU!!!!!!<BR>\n" );
document.write( "~~~~~~~~~~~~~~~~~~~~~~~~~\r<BR>\n" );
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document.write( "The equation x = 2x is incorrect. It should be x = 2z.\r<BR>\n" );
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document.write( "<PRE STYLE=\"white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;\"> \r\n" );
document.write( "So your system is\r\n" );
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document.write( "    x +     y +     z =  4000,   (1)\r\n" );
document.write( "2.85x + 3.10y + 3.35z = 12125,   (2)\r\n" );
document.write( "x = 2z.                          (3)\r\n" );
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document.write( "or\r\n" );
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document.write( "    x +     y +   x/2      =  4000,   (1')\r\n" );
document.write( "2.85x + 3.10y + 3.35*(x/2) = 12125    (2')\r\n" );
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document.write( "(no \"z\". \"z\" is just excluded).  Multiply (1') and (2') by 2 (both sides) and collect the like terms.\r\n" );
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document.write( "3x    + 2y    =  8000,       (3)\r\n" );
document.write( "9.05x + 6.20y = 24250.       (4)\r\n" );
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document.write( "I just did enough for you :=).\r\n" );
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document.write( "Can you complete on your own from this point?\r\n" );
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document.write( "Apply the substitution method. Express x from (3) an then substitute into (4).   Good luck !\r\n" );
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document.write( "Let me know if you still have problems.\r\n" );
document.write( "</PRE><BR>\n" );
document.write( " </SPAN>\n" );
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