Don't know password or answer question. Was gifted xbox360 with a parental lock

I'm the owner of the Teenage account but not the Parent Account.

I know the password for the Parent Account.

and yes, I would answer the questions.

how to remove xbox360 parental lock

The only way to remove the parental lock is by knowing the pass code, answering the security question if you forgot the pass code, or have the parent call
Microsoft Phone Support.

If for some reason you are unable to remember the code to access the settings to change it, the only other way to reset the code would be to contact Official Support. You can do this via http://support.xbox.com/contactus

Put in the code incorrectly, and it will take you to an option to reset this.

You will need to know the email used.

Hope this helps.