document.write( "Question 1185430: how old is jack and kylie's grandfather? the digits of his age add to 15, his age is an even number, he is younger than 90 \n" ); document.write( "
Algebra.Com's Answer #816253 by ikleyn(52782)\"\" \"About 
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\n" ); document.write( "\n" ); document.write( "There is only one two-digit even positive integer number less than 90 with the sum of digits 15.\r
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document.write( "    The proof is OBVIOUS.\r\n" );
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document.write( "    The last digit must be even, and there is only one working possibility for it, which is \"8\".\r\n" );
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document.write( "    Hence, the tens digit is  15-8 = 7.\r\n" );
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\n" ); document.write( "\n" ); document.write( "So the grandfather's age is 78 years.\r
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\n" ); document.write( "\n" ); document.write( "Probably, the question's accurate form should be \r
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\n" ); document.write( "\n" ); document.write( "        how old is jack's and kylie's grandfather?       (meaning one grandfather to two grandchild)\r
\n" ); document.write( "\n" ); document.write( "        the digits of his age add to 15, his age is an even number, he is younger than 90.\r
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