A merchant bought 1200 items for ₹1,800 and he sold them at the rate of 1000 for ₹1,600. Calculate gain or loss percentage.

A

$$\frac{20}{3}\%$$ los

B

$$\frac{30}{7}\%$$ los

C

$$\frac{20}{3}\%$$ gain

D

$$\frac{30}{7}\%$$ gain