If a 7-11 store is open 24 hours a day, 7 days a week, 365 days a year, then why are there locks on the doors?

Well, the problem states '365 days a year'.
If you have a leap year there will be 366 days that year, so it will have to close for one day, hence needing the locks.

If you say that a year is 365 1/4 days long, then it will still need to close for six hours a year.

Posted by Lewis on 2003-07-04 21:31:36