puzzle

1    A shopkeeper is selling his goods at a profit of 25%. One day a customer bought a toy worth Rs 400. The customer gave the shopkeeper a Rs 500 note. Since the shopkeeper did not have the change, he went to the next shopkeeper for help. His neighbouring shopkeeper gave him 5 notes of Rs 100 after taking the Rs 500 note from the him. The shopkeeper then returned Rs 100 to the customer. In the evening the neighbouring shopkeeper came back to the shop and told the shopkeeper that the Rs 500 note that he had given to him is fake. The shopkeeper promptly returned him a fresh Rs 500 note. How much money did the shopkeeper loose?

A) 500                   B) 920                    C) 600                    D) 1000