Which one of the following is a correct equation?

Opening Capital = Closing Capital + Drawings - Additional Capital - Profit + Loss

1. The opening balance is the balance that is brought forward at the beginning of an accounting period from the end of a previous accounting period or when starting out. 
2. The opening balance is the number of funds in a company's account at the beginning of a new financial period.
3. It is the first entry in the accounts, either when a company is first starting up its accounts or after a year-end.
4. In an operating firm, the ending balance at the end of one month or year becomes the opening balance for the beginning of the next month or accounting year.
5. The opening balance may be on the credit or debit side of the ledger.
6. Opening Capital = Closing Capital + Drawings - Additional Capital - Profit + Loss

Thus, option 3 is the correct answer.