Let $d$ be Grogg's dad's age currently and $g$ be Grogg's age currently. We get the following equations from the problem: \begin{align*}
d - 7 &= 7(g-3) \\
d-7&=7g-21 \\
0&=7g-d-14 \\
d&=7g-14 \\
d&=7(g-2) \\
d-7&=12(g-7) \\
d-7&=12g-84 \\
0&=12g-d-77
\end{align*} We write the ages in terms of Grogg's age to get a system of equations. Solving this system, we find that $g=\frac{7}{3}$ so $d = 7\cdot \frac{7}{3}-14 = 9\frac13 = \boxed{9.333}.$
Seven years ago, Grogg's dad was $12$ times as old as Grogg. Three years ago, Grogg's dad was $7$ times as old as Grogg. How old is Grogg's dad currently?
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