document.write( "Question 1006334: A jar contains nickles and pennies. If there are 56 coins in all and the total value is $1.52, How many nickles are in the jar?
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Algebra.Com's Answer #622480 by Edwin McCravy(20056) $\"\"$ $\"About$

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document.write( "Let the number of nickles be x\r\n" );
document.write( "Let the number of pennies be y\r\n" );
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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( "nickles       x      $0.05     $0.05x\r\n" );
document.write( "pennies       y      $0.01     $0.01y\r\n" );
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document.write( "TOTALS       56      -----     $1.52\r\n" );
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document.write( " The first equation comes from the second column.\r\n" );
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document.write( "  \r\n" );
document.write( "                 x + y = 56\r\n" );
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document.write( " The second equation comes from the last column.\r\n" );
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document.write( "           0.05x + 0.01y = 1.52\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 + 1y = 152\r\n" );
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document.write( " So we have the system of equations:\r\n" );
document.write( "           .\r\n" );
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document.write( "We solve by substitution.  Solve the first equation for y:\r\n" );
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document.write( "           x + y = 56\r\n" );
document.write( "               y = 56 - x\r\n" );
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document.write( "Substitute (56 - x) for y in 5x + 1y = 152\r\n" );
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document.write( "  5x + 1(56 - x) = 152\r\n" );
document.write( "    5x + 56 - 1x = 152\r\n" );
document.write( "         4x + 56 = 152\r\n" );
document.write( "              4x = 96\r\n" );
document.write( "               x = 24 = the number of nickles.\r\n" );
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document.write( " Substitute in y = 56 - x\r\n" );
document.write( "               y = 56 - (24\r\n" );
document.write( "               y = 32 pennies.\r\n" );
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document.write( "The number of pennies is 56-x or 56-24 or 32 pennies.\r\n" );
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document.write( "Checking:  24 nickles is $1.20 and 32 pennies is $0.32\r\n" );
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document.write( "            That's 56 coins.\r\n" );
document.write( "            And indeed $1.20 + $0.32 = $1.52\r\n" );
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document.write( "Edwin

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