The sum of present ages of A and B is 48 years. Today B is 4 years older than C. The respective ratio of the present ages of A and C is 4 : 7. What was B’s age two years ago.

30 years

Let present age of B = x

Prsent age of A = 48 - x

Age of C = x - 4

A : C = 4 : 7

\(\frac{48 - x}{x - 4}\) = \(\frac{4}{7}\)

7(48 - x)   =  4(x - 4) 

336 - 7x = 4x - 16 

11x = 352 

x = 32 

B's age two years ago = 32 - 2 = 30 years