document.write( "Question 1179739: The total price of 4 pens and 2 copies is rs 160 and that pen
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Algebra.Com's Answer #809313 by ikleyn(52788) $\"\"$ $\"About$

You can put this solution on YOUR website!
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document.write( "    4p + 2c = 160     (1)\r\n" );
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document.write( "    5p + 6c = 270     (2)\r\n" );
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document.write( "Multiply equation (1) by 3 (both sides).  Keep equation (2) as is.\r\n" );
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document.write( "    12p + 6c = 480    (1')\r\n" );
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document.write( "     5p + 6c = 270    (2')\r\n" );
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document.write( "From equation (1') subtract equation (1').  Doing this way, you eliminate the terms \"6c\", which cancel each other.\r\n" );
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document.write( "    12p - 5p = 480 - 270\r\n" );
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document.write( "        7p   = 210\r\n" );
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document.write( "         p   = 210/7 = 30.\r\n" );
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document.write( "To find \"c\", substitute the found value p= 30 into equation (1)\r\n" );
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document.write( "    4*30 + 2c = 160\r\n" );
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document.write( "    120  + 2c = 160\r\n" );
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document.write( "          2c  = 160 - 120 = 40\r\n" );
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document.write( "           c  = 40/2 = 20.\r\n" );
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document.write( "ANSWER.  A pen price is rs 30;  a copy price is  rs 20 for each.\r\n" );
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\n" ); document.write( "\n" ); document.write( "The method I used in my solution is called \"the Elimination method\".\r
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\n" ); document.write( "\n" ); document.write( "You may check my solution on your own by substituting the found values into the original equations.\r
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