document.write( "Question 896327: The difference between a 2- digit number and the number obtained by interchanging its digits is 27. What is the difference between the sum and the difference of the digits of the number if the ratio between the digits of the number is 1:2 ? \n" ); document.write( "
Algebra.Com's Answer #543431 by Edwin McCravy(20056)\"\" \"About 
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The difference between a 2- digit number and the number obtained by interchanging its digits is 27.
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document.write( "\"%2810t%2Bu%29-%2810u%2Bt%29+=+27\"\r\n" );
document.write( "\"10t%2Bu-10u-t+=+27\"\r\n" );
document.write( "\"9t-9u+=+27\"\r\n" );
document.write( "\"t-u+=+3\"\r\n" );
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document.write( "This tells us that t is larger than u, which we'll need\r\n" );
document.write( "to know for the next part:\r\n" );
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document.write( "...the ratio between the digits of the number is 1:2 ?\r\n" );
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document.write( "Since t is larger than u we know that this means\r\n" );
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document.write( "\"u%2Ft=1%2F2\" and not \"cross%28t%2Fu=1%2F2%29\"\r\n" );
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document.write( "\"u%2Ft=1%2F2\"\r\n" );
document.write( "\"2u=t\"\r\n" );
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document.write( "So we have the system of two equations:\r\n" );
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document.write( "\"system%28t-u=3%2C2u=t%29\"\r\n" );
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document.write( "Solve by substituting:\r\n" );
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document.write( "\"t-u=3\"\r\n" );
document.write( "\"2u-u=3\"\r\n" );
document.write( "\"u=3\"\r\n" );
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document.write( "\"2u=t\"\r\n" );
document.write( "\"2%283%29=t\"\r\n" );
document.write( "\"6=t\"\r\n" );
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document.write( "So the number is 63.\r\n" );
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document.write( "Edwin
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