document.write( "Question 276430: Shelly is three years older than Michele. Four years ago the sum of their ages was 67. Find the age of the person now. Can you give me a basic formula to solving most Age Word Problems. \n" ); document.write( "

Algebra.Com's Answer #201447 by oberobic(2304) $\"\"$ $\"About$

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S = Shelly's age
\n" ); document.write( "M = Michele's age
\n" ); document.write( "S = M + 3 :: Shelly is 3 years older than Michele.
\n" ); document.write( ".
\n" ); document.write( "\"Four years ago\" their ages will be S-4 and M-4. The sum of their ages was 67.
\n" ); document.write( "So, today we can say
\n" ); document.write( "S-4 + M-4 = 67
\n" ); document.write( "S + M -8 = 67
\n" ); document.write( "S + M = 75
\n" ); document.write( ".
\n" ); document.write( "Substitute S = M+3
\n" ); document.write( ".
\n" ); document.write( "(M+3) + M = 75
\n" ); document.write( "2M + 3 = 75
\n" ); document.write( "2M = 72
\n" ); document.write( "M =36
\n" ); document.write( "S = M+3 = 39
\n" ); document.write( ".
\n" ); document.write( "Four years ago their ages were:
\n" ); document.write( "S = 39 -4 = 35
\n" ); document.write( "M = 36 - 4 = 32
\n" ); document.write( ".
\n" ); document.write( "Checking if the sum 4 years ago = 67.
\n" ); document.write( "35 + 32 = 67
\n" ); document.write( "Yes.
\n" ); document.write( ".
\n" ); document.write( "Answer:
\n" ); document.write( "Shelly is 39, and Michele is 36.
\n" ); document.write( ".
\n" ); document.write( "Done \n" ); document.write( "

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