document.write( "Question 158853: The sum of the digits of a two-digit number is 7. When the digits are reversed, the number formed is 27 more than the original number. Find the original number.
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Algebra.Com's Answer #117012 by nerdybill(7384)\"\" \"About 
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The sum of the digits of a two-digit number is 7. When the digits are reversed, the number formed is 27 more than the original number. Find the original number.
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\n" ); document.write( "Let x = ones digit
\n" ); document.write( "and y = tens digit
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\n" ); document.write( "from: \"The sum of the digits of a two-digit number is 7.\"
\n" ); document.write( "x+y =7 (equation 1)
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\n" ); document.write( "from: \"When the digits are reversed, the number formed is 27 more than the original number.\"
\n" ); document.write( "10x + y = (10y + x) + 27
\n" ); document.write( "9x = 9y + 27
\n" ); document.write( "x = y + 3 (equation 2)
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\n" ); document.write( "Solve equation 1 for y:
\n" ); document.write( "x+y =7
\n" ); document.write( "y =7-x
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\n" ); document.write( "Substitute the above into equation 2 and solve for x:
\n" ); document.write( "x = y + 3
\n" ); document.write( "x = 7-x + 3
\n" ); document.write( "2x = 7+3
\n" ); document.write( "2x = 10
\n" ); document.write( "x = 5 (ones digit)
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\n" ); document.write( "Subsitute the above into equation 1 and solve for y:
\n" ); document.write( "x+y =7
\n" ); document.write( "5+y =7
\n" ); document.write( "y = 7-5
\n" ); document.write( "y = 2
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\n" ); document.write( "Solution: The original number is 27 \n" ); document.write( "
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