Rajan got married 8 years ago. His present age is 6/5 times his age at the time of his marriage. Rajan's sister was 10 years younger to him at the time of his marrige. The age of Rajan's sister is = ?

Answer: Option C

Let Rajan's age 8 years ago be x years,
Then, present age = (x + 8) years
$$\begin{array}{rl}& \therefore x+8=\frac{6}{5}x\\ & \Rightarrow 5x+40=6x\\ & \Rightarrow x=40\end{array}$$
Rajan's sister's age 8 years ago
= (40 - 10) years
= 30 years
∴ His sister's age now
= (30+8) years
= 38 years