The ration of the father’s age to his son’s age is 7:3.The product of their ages is 756.The ratio of their ages after 6 years will be : Choices.
A) 5 : 2	B) 2 : 1	C) 11 : 7	D) 13 : 9	E) none of these

Rationale: solution let the present ages of the father and son be 7 x and 3 x years respectively . then , 7 x 3 x = 756 ⇔ 21 x 2 = 756 ⇔ x 2 = 36 ⇔ x = 6 . ∴ required ratio = ( 7 x + 6 ) : ( 3 x + 6 ) = 48 : 24 = 2 : 1 . answer b
Answer: B