If the amount of profit earned by Company A in 2006 was Rs. 10.12 lakh, what was the total investment?

Answer: Option E

Let the investment of A in 2006 be Rs. $$x$$
Then,
\begin{aligned} & \text{Profit = 55% of Rs. }x \\ & =\text{Rs.}\left(x\times\frac{55}{100}\right) \\ & =\text{Rs.}\left(\frac{11x}{20}\right) \\ & \therefore \frac{11x}{20} = 10.12\text{ lakh} \\ & \Rightarrow \frac{11x}{20} = 10.12\times100000 \\ & \Rightarrow \frac{11x}{20} = 1012000 \\ & \Rightarrow x = 1012000\times\frac{20}{11} \\ & \Rightarrow x = 1840000 \\ & \Rightarrow x = \text{18.4 lakh} \\\end{aligned}
  $$\Rightarrow$$ Investment of A in 2006 = 18.4 lakh