The ceiling of Katie’s living room is a square that is 25 ft long on each side. To decorate for a party, she plans to hang crepe paper around the perimeter of the ceiling and then from each corner to the opposite corner. (just 2 diagonals) Katie can buy rolls that each contain 30 ft of crepe paper. What is the minimum number of rolls she should buy?
(assume the crepe paper is hung flush with the wall and ceiling)