The ratio between the present ages of P and Q is 6 : 7. If Q is 4 years old than P, what will be the ratio of the ages of P and Q after 4 years ?

\par Let P's age and Q's age be 6x years and 7x years respectively.

\par Then, 7x - 6x = 4

x = 4

\par Required ratio = (6x + 4) : (7x + 4) = 28 : 32 = 7 : 8