document.write( "Question 1098024: How many three digit integers are increased by exactly 99 when the digits are reversed? \n" ); document.write( "

Algebra.Com's Answer #712423 by ikleyn(52832) $\"\"$ $\"About$

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\n" ); document.write( "The necessary and sufficient condition for it is that\r
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document.write( "    The \"ones\" digit is 1 more than the \"hundreds\" digit.\r\n" );
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document.write( "    And if this condition is in place, then it does not matter what the \"tens\" digit is.\r\n" );
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\n" ); document.write( "\n" ); document.write( "Based on it, all the 3-digit numbers\r
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document.write( "     1x2,  2x3,  3x4,  4x5,  5x6,  6x7,  7x8,  8x9  \r\n" );
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\n" ); document.write( "\n" ); document.write( "work, for any x = 0, 1, 2, 3, 4, 5, 6, 7, 8, 9.\r
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\n" ); document.write( "\n" ); document.write( "In all, you have 10*8 = 80 numbers satisfying the condition.\r
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