A shopkeeper sells an article at Rs. 40 and gets X% profit. However, when he sells it at Rs. 20, he faces same percentage of loss. What is the original cost of the article?

- Rs. 10
- Rs. 20
- Rs. 30
- Rs. 40

### Answer

Profit and loss is calculated on the cost price. Let the cost price of the article be P.

Profit % = Loss %

(40 - P)/P = (P - 20)/P

2P = 60

P = 30

**The correct option is C.**