document.write( "Question 252792: In the addition problem below, each letter represents a different single digit.\r
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Algebra.Com's Answer #184874 by Edwin McCravy(20055) $\"\"$ $\"About$

You can put this solution on YOUR website!
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document.write( "Let the \"carry\" number be x, which is either 0 or 1\r\n" );
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document.write( "   x\r\n" );
document.write( "   CB\r\n" );
document.write( "  +AA\r\n" );
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document.write( "  CCC\r\n" );
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document.write( "Then we have this system:\r\n" );
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document.write( "or\r\n" );
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document.write( "The second equation becoms:\r\n" );
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document.write( "C cannot be 0, and x can only be no larger than 1,\r\n" );
document.write( "therefore C can be no larger than 1, since A is less\r\n" );
document.write( "than 20.  So C must be 1 and x must be 1 since A must\r\n" );
document.write( "be less than 10. So C =1, x=1 and A = 10(1) - 1 = 9\r\n" );
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document.write( "Substituting in\r\n" );
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document.write( "B + A = 10x + C\r\n" );
document.write( "B + 9 = 10(1) + 1\r\n" );
document.write( "B + 9 = 10 + 1\r\n" );
document.write( "B + 9 = 11\r\n" );
document.write( "    B = 2\r\n" );
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document.write( "Thus the solution is:\r\n" );
document.write( " 1\r\n" );
document.write( " 12\r\n" );
document.write( "+99\r\n" );
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document.write( "111\r\n" );
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document.write( "Edwin

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