document.write( "Question 715170: I am trying to solve the following problem using a system of equations.
\n" ); document.write( "1. A collection of nickels and quarters is worth 4.65. There are 3 more nickels than quarters. Use a system of equations to determine how many coins are in the collection.
\n" ); document.write( "I have n+q=4.65, and (3+n(.05))+ q(.25)=total coins, but how do I solve this?
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Algebra.Com's Answer #439252 by Edwin McCravy(20055)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "Your error is in adding coins and getting dollars.\r\n" );
document.write( "You can't do that.  \r\n" );
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\n" ); document.write( "A collection of nickels and quarters is worth 4.65.
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document.write( "That translates as the MONEY equation\r\n" );
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document.write( "   ($.05)n + ($.25)q = $4.65\r\n" );
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\n" ); document.write( " There are 3 more nickels than quarters.
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document.write( "That translates as the COIN equation:\r\n" );
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document.write( "                  n = q + 3\r\n" );
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document.write( "So the system is\r\n" );
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document.write( "        .05n + .25q = 4.65\r\n" );
document.write( "                  n = q + 3\r\n" );
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document.write( "You can simplify the first equation by clearing of decimals\r\n" );
document.write( "by multiplying through by 100\r\n" );
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document.write( "           5n + 25q = 465\r\n" );
document.write( "                  n = q + 3\r\n" );
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document.write( "Substitute q + 3 for n in the first equation:\r\n" );
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document.write( "           5n + 25q = 465\r\n" );
document.write( "     5(q + 3) + 25q = 465\r\n" );
document.write( "      5q + 15 + 25q = 465\r\n" );
document.write( "           30q + 15 = 465\r\n" );
document.write( "                30q = 450\r\n" );
document.write( "                  q = 15\r\n" );
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document.write( "Substitute 15 for q in \r\n" );
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document.write( "                  n = q + 3\r\n" );
document.write( "                  n = 15 + 3\r\n" );
document.write( "                  n = 18\r\n" );
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document.write( "So there were 18 nickels and 15 quarters.\r\n" );
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document.write( "Edwin
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