A shopkeeper earns a profit of 10% after allowing a discount of 20% on the marked price. The cost price of the article whose marked price is Rs. 880, is = ?

Answer: Option B

Market price of the article = Rs. 880
After discount selling price of the article
$$\begin{array}{rl}& \text{ = }\frac{880\times 80}{100}\\ & \text{ = Rs}\text{. 704}\\ & \text{Cost price of the article }\\ & \text{ = }\frac{704\times 100}{110}\\ & =\text{Rs}\text{. 640}\end{array}$$