A Lady (L) bought an item of Rs 100 from the Shopkeeper (C). She paid him through a 500 Rs Note. Realizing that he did not have change, the shopkeeper (C) got change for that note from another Shopkeeper (S) and paid Rs 400 to the Lady. After a few days, Shopkeeper (S) realized that the note is fake, and this railed at Shopkeeper (C) and took 500 Rs back from him.
So in this whole process how much money did Shopkeeper (C) loose in the end?