document.write( "Question 924248: Mackenzie has 19 coins in her pocket. They are all either dimes or quarters, totaling $3.40.\r
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Algebra.Com's Answer #560718 by Edwin McCravy(20056) $\"\"$ $\"About$

You can put this solution on YOUR website!
Mackenzie has 19 coins in her pocket. They are all either dimes or quarters, totaling $3.40.
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document.write( "Let the number of dimes be D\r\n" );
document.write( "Let the number of dimes be Q   \r\n" );
document.write( "                      Value      Value\r\n" );
document.write( "Type       Number       of         of\r\n" );
document.write( " of          of        EACH       ALL\r\n" );
document.write( "coin        coins      coin      coins\r\n" );
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document.write( "DIMES        D        $0.10    $0.10D \r\n" );
document.write( "QUARTERS     Q        $0.25    $0.25Q\r\n" );
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document.write( "TOTALS      19        -----    $3.40\r\n" );
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document.write( " The equations comes from the \"Number of coins\" column \r\n" );
document.write( "and the \"Value of ALL coins\" column:\r\n" );
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document.write( "  \r\n" );
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document.write( "Get rid of decimals in the second by multiplying \r\n" );
document.write( "every term by 100\r\n" );
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document.write( "    10D + 25Q = 340\r\n" );
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document.write( "Solve the first for D\r\n" );
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document.write( "D+Q=19\r\n" );
document.write( "  D=19-Q\r\n" );
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document.write( "Substitute in\r\n" );
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document.write( "     10D + 25Q = 340\r\n" );
document.write( "10(19-Q) + 25Q = 340\r\n" );
document.write( " 190-10Q + 25Q = 340\r\n" );
document.write( "       190+15Q = 340\r\n" );
document.write( "           15Q = 150 \r\n" );
document.write( "             Q = 10 quarters\r\n" );
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document.write( "             D = 19-Q = 19-10 = 9 dimes\r\n" );
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document.write( "Edwin

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