document.write( "Question 1051301: An office has some 20¢ stamps and some 28¢ stamps. Altogether the office has 210 stamps for a total value of $47.60. How many of each type of stamp does the office have?
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Algebra.Com's Answer #666883 by ikleyn(52786) $\"\"$ $\"About$

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\n" ); document.write( "An office has some 20¢ stamps and some 28¢ stamps. Altogether the office has 210 stamps for a total value of $47.60.
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\n" ); document.write( "\n" ); document.write( "Solution 1. One equation in one unknown\r
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document.write( "Let x be the number of the 20c stamps.\r\n" );
document.write( "Then the number of the 28c stamps is (210-x).\r\n" );
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document.write( "A \"value\" equation is\r\n" );
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document.write( "20x + 28*(210-x) = 4760.       (1)   (4760 = $47.60 )\r\n" );
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document.write( "Simplify and solve for x.\r\n" );
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\n" ); document.write( "\n" ); document.write( "Solution 2. System of two equations in two unknowns\r
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document.write( "  x +   y =  210,          (1)\r\n" );
document.write( "20x + 28y = 4760.          (2)\r\n" );
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document.write( "From (1) express y = 210-x and substitute it into (2). You will get and equation\r\n" );
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document.write( "20x + 28*(210-x) = 4760.   (3)\r\n" );
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document.write( "It is identical to the equation (1) in the Solution 1 above.\r\n" );
document.write( "Simplify it and solve for x.\r\n" );
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document.write( "After finding x calculate y.\r\n" );
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