document.write( "Question 1209080: Seven years ago, Grogg's dad was 9 times as old as Grogg. Three years ago, Grogg's dad was 2 times as old as Grogg. How old is Grogg's dad currently? \n" ); document.write( "

Algebra.Com's Answer #847648 by math_tutor2020(3817) $\"\"$ $\"About$

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	7 years ago	3 years ago
Grogg’s age	x	x+4
The dad’s age	9x	2(x+4) = 2x+8

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\n" ); document.write( "\n" ); document.write( "7 years ago, Grogg's age was x years old.
\n" ); document.write( "His dad's age was 9x since its 9 times that of his son's age.\r
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\n" ); document.write( "\n" ); document.write( "Fast forward 4 years so we arrive at the \"3 years ago\" timestamp.
\n" ); document.write( "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.\r
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\n" ); document.write( "\n" ); document.write( "7 years ago the dad was 9x years old.
\n" ); document.write( "3 years ago the dad was 2x+8 years old.
\n" ); document.write( "This is a gap of 4 years, so subtracting these previous ages should get us 4.\r
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\n" ); document.write( "\n" ); document.write( "(2x+8) - 9x = 4
\n" ); document.write( "Solving this equation leads to x = 4/7 = 0.571429 approximately\r
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\n" ); document.write( "\n" ); document.write( "Since this isn't a whole number, there might be a typo somewhere in your question.
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