The correct answer to this open question is the following.
In the set of all past due accounts, let the event A mean the account is between 31 and 60 days past due and event B means the account is that of a new customer. The complement of A is all accounts fewer than 31 or more than 60 days past due.
That is why is so important to maintain a good credit score. A past-due account was not paid on time and with the minimum amount of money it was required. So pay attention to the last day marked in your account statement. It is not a good thing to your record and you will be paying extra money due to a late fee.
