A trader professes to sell his goods at the cost price at a loss of 8% but weight 900 grams in place of a kg weight. find his loss OR gain percentage

Assume seller says that his cost is Rs. 1000 for 1000 grams and he sells is at Rs. 920 at 8% loss. But, actually he is selling only 900 grams which costed him Rs. 900. Therefore, he is earning a profit of Rs. 20 on his actual cost of Rs. 900. So, Profit percentage=20/900*100=2.22%

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2.22 % gain

20/9?