document.write( "Question 117904: my daughter asked how old i am, i answered, 'in 20 years i'll be twice as old as i was 12 years ago.'How old am i now? \n" ); document.write( "
Algebra.Com's Answer #85898 by Edwin McCravy(20056)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "my daughter asked how old i am, i answered, 'in 20 years i'll be twice\r\n" );
document.write( "as old as i was 12 years ago.'How old am i now?\r\n" );
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document.write( "1. First I'll tell you the answer.  \r\n" );
document.write( "2. Then I'll show you how to check it.\r\n" );
document.write( "3. Then I'll tell you how to find it.\r\n" );
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document.write( "1. The answer is \"I am 44 now\"\r\n" );
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document.write( "2. I am 44 years old.  In 20 years I'll be 64. 12 years ago I was 32.  \r\n" );
document.write( "   And 64 = 2 times 32.\r\n" );
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document.write( "3. I am x years old.  In 20 years I'll be x+20.  12 years ago I was x-12.\r\n" );
document.write( "   And x+20 = 2 times x-12.\r\n" );
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document.write( "   So:\r\n" );
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document.write( "   x + 20 = 2(x - 12)\r\n" );
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document.write( "Solve that and you'll get 44.\r\n" );
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document.write( "Do you see that from 2 and 3 that often setting up a word problem\r\n" );
document.write( "is exactly the same process as checking it when you know the answer?\r\n" );
document.write( "Just \"check\" it using x.  Then solve.\r\n" );
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document.write( "Edwin
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