You see an item you want to buy for $97 but you don’t have any money so you borrow $50 from your mom and $50 from your auntie you buy the item and you have three dollars of change you give your mom one dollar and you give your aunty one dollar you keep a dollar for yourself you know your mom $49 and your auntie $49 but $49 plus $49 equals $98 and you onlyKept one dollar so where is the missing one dollar