How to Find the Administrator Password on a Mac
As with the Windows operating system, all of your user account sign-in information is stored within the memory of your hard drive. This includes the password for your administrator account. This information is always accessible on your hard drive via native Mac OS X tools---you just have to know which tools to open and where to look within them in order to retrieve the information that you desire.
Open your Mac OS X "Finder."
Double-click "Keychain Access" to open the native Mac OS X utility.
Click on the user account for which you want to find the password. Click "Show Password" to bring up the password for that particular account.