A starts business with Rs. 3500 and after 5 months, B joins with A as his partner. After a year, the profit is divided in the ratio 2 : 3. What is B's contribution in the capital?

Answer: Option D

Let B's capital be Rs. x
∴ A's share in 12 months = 3500 × 12
And, B's share in 7 months = 7x
$$\begin{array}{rl}& \text{Then},\frac{3500\times 12}{7x}=\frac{2}{3}\\ & \Rightarrow 14x=126000\\ & \Rightarrow x=9000\end{array}$$