A dishonest dealer defrauds to the extent of x % in buying as well as selling his goods by using faulty weight. What will be the gain percent on his outlay?

A

$$2x \%$$

B

$$\left(\frac{10}{x} + x^2\right)\%$$

C

$$\left(2x + \frac{x^2}{100}\right)\%$$

D

$$\left(x + \frac{x^2}{100}\right)\%$$