human
Tracy has been collecting novels from her friends to donate to the Children For The Future charity organization. In the first week she collects a certain number of books. In the next five weeks, she collects ten times as many books as she did in the first week. How many books did she collect in the first week if she has 99 books now?
assistant
How many books does Tracy have after six weeks? ** Let's say the number of books she had in the first week is x. After six weeks, Tracy has x + x*10 = 99 books.
How many books does Tracy have after six weeks? ** Combining like terms, we get 11x = 99
How many books did Tracy have in the first week? ** Dividing both sides by 11, we find that the number of books Tracy had in the first week is x = 9
#### 9