An article is sold at a loss of 10%. Its cost price is Rs.800. A discount of 20% was offered on the labelled price while selling. What is the loss per cent at the labelled price ?

Let labelled price of the item = $$Rs. 100x$$

Discount % = 20%

=> Selling price = $$100x-\frac{20}{100} \times 100x = Rs. 80x$$

Cost price = Rs. 800

Loss % = $$\frac{800-80x}{800} \times 100=10$$

=> $$\frac{800-80x}{8}=10$$

=> $$100-10x=10$$

=> $$10x=100-10=90$$

=> $$x=\frac{90}{10}=9$$

Thu, labelled price = $$100 \times 9 = Rs. 900$$

and Selling price = $$80 \times 9 = Rs. 720$$

$$\therefore$$ Loss % at labelled price = $$\frac{900-720}{900} \times 100$$

= $$\frac{180}{9}=20\%$$

=> Ans - (C)