Christmas Grocery hoursAlgebra Level 2
In Australia, shops are required to remain closed on Christmas day, December 25. (They are also closed Good Friday, but that is irrelevant to this problem).
The grocery store that I go to is open from 10am to 8pm every weekday, and 8am to 10pm every weekend.
From December 22 to 28 in 2013 (inclusive), how many hours is the grocery shop open for?