Ratio of A's age to B's age is 4 : 3. 'A' will be 26 years old after 6 years. The age of B now is = ?

Answer: Option D

Ratio of A's age to B's age is 4 : 3 = 4x : 3x
After 6 years A's age = 4x + 6
∴ According to question,
$$\begin{array}{rl}& 4x+6=26\\ & \boxed{x=5}\\ & \therefore \text{B’s age}=3x\\ & =3\times 5\\ & =15\end{array}$$