# A man invested 1/3 of his capital at 7%, 1/4 at 8% and the remainder at 10%. If his annual income is Rs. 561, the capital is?

A. Rs. 5400 B. Rs. 6000 C. Rs. 6600 D. Rs. 7200 Answer: Option C
Let total capital be Rs. x Then, $\begin{array}{l}\Rightarrow\left(\frac{x}{3}\times\frac{7}{100}\times1\right)+\left(\frac{x}{4}\times\frac{8}{100}\times1\right)+\left(\frac{5x}{12}\times\frac{10}{100}\times1\right)=561\\ \Rightarrow\frac{7x}{300}+\frac{x}{50}+\frac{x}{24}=561\\ \Rightarrow51x=(561\times600)\\ \Rightarrow x=\left(\frac{561\times600}{51}\right)\\ =6600\end{array}$