Explanation:

As per the question,
Simple Interest $$\dfrac{x\times R \times T}{100}=\dfrac{x\times12\times 2}{100}=0.24x$$
Compound Interest $$x(1+\dfrac{R}{100})^T-x=x (1+\dfrac{12}{100})^2-x=x\times1.12\times 1.12-x=0.2544x$$
Hence the difference between Simple interest and compound interest $$\Rightarrow 0.2544x-0.24x=0.01x$$
$$\Rightarrow 0.0144x=43.2$$
Hence $$x=\dfrac{43.2 \times 10000}{144}=3000$$Rs.