document.write( "Question 7352: Tom's father is three times as old as Tom. Four years ago Tom's father was four times as old as Tom. How old is Tom? \n" ); document.write( "

Algebra.Com's Answer #4086 by AnlytcPhil(1806) $\"\"$ $\"About$

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Tom's father is three times as old as Tom. Four years ago
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document.write( "Let:
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document.write( "Tom's age now = T
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document.write( ">>...Tom's father is three times as old as Tom...<<
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document.write( "TRANSLATION:
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document.write( "Tom's father's age now = 3T
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document.write( "Then 
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document.write( "Tom's age four years ago = T-4
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document.write( "and
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document.write( "Tom's father's age four years ago = 3T-4
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document.write( ">>... Four years ago Tom's father was four times as old as Tom...<<
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document.write( "TRANSLATION:
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document.write( "Tom's father's age four years ago = 4 times Tom's age 4 years ago
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document.write( "                             3T-4 = 4(T-4)
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document.write( "                             3T-4 = 4T-16
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document.write( "                            3T-4T = 4-16
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document.write( "                               -T = -12
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document.write( "                                T = 12
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document.write( "Check:
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document.write( "Tom is 12 years old.  His father is 3 times as old as Tom, or 36.
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document.write( "Four years ago, Tom was 8 and his father was 32.  So indeed Tom's father
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document.write( "was four times as old as Tom was then.\r
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document.write( "Edwin 
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document.write( "   
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