document.write( "Question 832822: Michael's bank contains only nickels, dimes and quarters. There are 63 coins in all valued at $5.50. The number of nickels is 5 short of being 3 times the sum of the number of dimes and quarters. How many dimes are in the bank \n" ); document.write( "
Algebra.Com's Answer #502210 by Edwin McCravy(20060)\"\" \"About 
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Michael's bank contains only nickels, dimes and quarters.
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document.write( "N = number of nickels\r\n" );
document.write( "D = number of dimes\r\n" );
document.write( "Q = the number of quarters
There are 63 coins in all
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document.write( "           N + D + Q = 63\r\n" );
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valued at $5.50.
The N nickels are worth $0.05N\r\n" );
document.write( "The D dimes are worth $0.10D\r\n" );
document.write( "The Q quarters are worth $0.25Q\r\n" );
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document.write( "0.05N + 0.10D + .25Q = 5.50\r\n" );
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document.write( "Multiply every term by 100 moves the decimals two places over:\r\n" );
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document.write( "      5N + 10D + 25Q = 550\r\n" );
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document.write( "Divide every term by 5\r\n" );
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document.write( "         N + 5D + 5Q = 110
The number of nickels is 5 short of being 3 times the sum of
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the sum of number of dimes and quarters = D+Q\r\n" );
document.write( "3 times the sum of number of dimes and quarters = 3(D+Q)\r\n" );
document.write( "5 short of being 3 times the sum of the number of dimes and quarters = 3(D+Q)-5\r\n" );
document.write( "So\r\n" );
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document.write( "                   N = 3(D+Q) - 5\r\n" );
document.write( "                   N = 3D + 3Q - 5\r\n" );
document.write( "         N - 3D - 3Q = -5\r\n" );
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document.write( "So we have the system of 3 equations in 3 unknowns:\r\n" );
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document.write( "         N +  D +  Q =  63\r\n" );
document.write( "         N + 2D + 5Q = 110 \r\n" );
document.write( "         N - 3D - 3Q =  -5\r\n" );
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document.write( "Solve that system by elimination.\r\n" );
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How many dimes are in the bank?
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document.write( "Solve the system and see.  If you can't post again\r\n" );
document.write( "asking how to solve it.\r\n" );
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document.write( "Edwin
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