document.write( "Question 940790: piggy bank consists of nickels and dimes. there are 30 coins worth $1.90, how many nickels and dimes are in the piggy bank \n" ); document.write( "

Algebra.Com's Answer #573417 by Edwin McCravy(20060) $\"\"$ $\"About$

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piggy bank consists of nickels and dimes. there are 30 coins worth $1.90, how many nickels and dimes are in the piggy bank\r
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document.write( "Let the number of nickels be x\r\n" );
document.write( "Then the number of dimes, using \r\n" );
document.write( "ONE PART = TOTAL MINUS OTHER PART,\r\n" );
document.write( "is 30-x.  \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( "NICKELS      x        $0.05    $0.05x \r\n" );
document.write( "DIMES      30-x       $0.10    $0.10(30-x)\r\n" );
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document.write( "TOTALS      30        -----    $1.90\r\n" );
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document.write( " The equation comes from the column on the right\r\n" );
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document.write( "  \r\n" );
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document.write( "0.05x + 0.10(30-x) = 1.90\r\n" );
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document.write( "Get rid of decimals by multiplying every term by 100\r\n" );
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document.write( "     5x + 10(30-x) = 190\r\n" );
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document.write( "    5x + 300 - 10x = 190\r\n" );
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document.write( "         -5x + 300 = 190\r\n" );
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document.write( "               -5x = -110\r\n" );
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document.write( "                 x = 22 = the number of nickels\r\n" );
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document.write( "The number of dimes is 30-x or 30-22 or 8 dimes.\r\n" );
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document.write( "Checking:  22 nickels is $1.10 and 8 dimes is $0.80\r\n" );
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document.write( "And indeed $1.10+$0.80 = $1.90.\r\n" );
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document.write( "Edwin

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