Present ages of X and Y are in the ratio 5 : 6 respectively. Seven years hence this ratio will become 6 : 7 respectively. What is X’s present age in years ?

\par Let the present ages of X and Y be 5x years and 6x years respectively.

\frac{5x + 7}{6x + 7} = \frac{6}{7}

7(5x + 7) = 6(6x + 7)

x = 7

\par X's present age = 5x = 35 years.