Question 1209080
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<table border = "1" cellpadding = "5"><tr><td></td><td>7 years ago</td><td>3 years ago</td></tr><tr><td>Grogg’s age</td><td>x</td><td>x+4</td></tr><tr><td>The dad’s age</td><td>9x</td><td>2(x+4) = 2x+8</td></tr></table>


7 years ago, Grogg's age was x years old. 
His dad's age was 9x since its 9 times that of his son's age.


Fast forward 4 years so we arrive at the "3 years ago" timestamp.
At this point Grogg was x+4 years old and his dad was twice his age, so the dad was 2(x+4) = 2x+8 years old.


7 years ago the dad was 9x years old.
3 years ago the dad was 2x+8 years old.
This is a gap of 4 years, so subtracting these previous ages should get us 4.


(2x+8) - 9x = 4
Solving this equation leads to x = 4/7 = 0.571429 approximately


Since this isn't a whole number, there might be a typo somewhere in your question. 
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