Let, present age of father = F years and present age of son = S years According to the question (F-1)= 4(S-1) ⇒F-1 = 4S-4 ⇒ F-4S= -3 .......(i) and (F+6) = 2(S+6) + 9 ⇒ F+6 = 2S +12+9 ⇒F-2S=21-6 ⇒F-2S = 15 ....(ii) Now, solving Eqs, (i) and (ii) we have F= 33 Years and S = 9 Years ∴ Ratio of their present ages = 33:9 = 11 : 3