document.write( "Question 664271: Don is 3 more than the age of tom and in 9 years, he will be 3 times as old as tom was 4 years ago. what is the age of Don?
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Algebra.Com's Answer #413268 by ankor@dixie-net.com(22740) $\"\"$ $\"About$

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Don is 3 more than the age of tom,
\n" ); document.write( " d = t + 3
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\n" ); document.write( " t = d - 3
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\n" ); document.write( " and in 9 yrs he will be 3 times as old as tom was 4 years ago.
\n" ); document.write( "d + 9 = 3(t-4)
\n" ); document.write( "d + 9 = 3t - 12
\n" ); document.write( "d = 3t - 12 - 9
\n" ); document.write( "d = 3t - 21
\n" ); document.write( "replace t with (d-3)
\n" ); document.write( "d = 3(d-3) - 21
\n" ); document.write( "d = 3d - 9 - 21
\n" ); document.write( "d = 3d - 30
\n" ); document.write( "30 = 3d - d
\n" ); document.write( "30 = 2d
\n" ); document.write( "d = 30/2
\n" ); document.write( "d = 15 yrs is Don's age
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\n" ); document.write( "See if that checks out in the statement (Tom is 12 yrs old
\n" ); document.write( "\"In 9 yrs he will be 3 times as old as tom was 4 years ago.\"
\n" ); document.write( "15 + 9 = 3(12 - 4)
\n" ); document.write( "24 = 3(8) \n" ); document.write( "

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