ATQ, Let the present ages of 'P' and 'Q' be '9a' years and '13a' years, respectively. We know that, difference between the ages of two people remains same. ATQ, 13a - 9a = 12 Or, 4a = 12 So, 'a' = 3 Age of 'R' two years hence from now = [(2/3) X 9 X 3] + 2 = 20 years Present age of 'S' = (1/3) X 13 X 3 = 13 years Therefore, required % = [(20 - 13) ÷ 20] X 100 = 35%