+306 Seven years ago, Grogg's dad was $9$ times as old as Grogg. Four years ago, Grogg's dad was $6$ times as old as Grogg. How old is Grogg's dad currently?
+37146 (d-7) = 9 (g-7) Given
(d-4) = 6 (g-4) Given <==== solve for g= (d+20)/6 <==== use THIS in the first equation
d-7 = 9 ( (d+20)/6 - 7) Solve for d
d-7 = (9d+180)/6 - 63
d+56 = (9d+180)/6
6d + 336 = 9d + 180
156 = 3d
d = 52 y/o now
