document.write( "Question 240776: How do I write this problem into an equation:\r
\n" ); document.write( "\n" ); document.write( "Sean is 20 and his brother is 12. How many years ago was Sean three times as old as his brother?
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Algebra.Com's Answer #176385 by edjones(8007)\"\" \"About 
You can put this solution on YOUR website!
Let x be the number of years past.
\n" ); document.write( "(20-x) / (12-x) = 3
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