A man walks into book shop and buys $10 magazine, and paying it with a $100 dollar bill. The book shop owner does not have enough change ($90) for the hundred, so he goes over to the neighboring store (a bakery) to get change for the $100 that the man gave him. The book shop owner gives the man the $10 magazine and the $90 dollar change, and the man leaves. A little later, the owner from bakery goes to tell bookshop owner that the $100 bill was fake and demands a real $100 back. Bookshop owner compensates bakery owner for the $100 dollars. Now the question is: How much did bookshop owner lose in total