The Egyptians, and they had a lot of influence on the OT, believed in a 360 day year. They were, however, aware, that there were 365 days (I think they were not aware of the quarter), and told a tale of one of the gods envigling 5 extra days out of it by gambling with the light of the Moon (may not be quite accurate here) in order that new gods should be born, after Amun had cursed the mother with not being able to bear children on any day of the year. The resulting children were Isis, Osiris, Set, Nut and A.N.Other, and the extracalerary days festivals. This would create problems for a monotheist society.
Try doing maths with 365.24....... and the wish of the two cultures to use 360 becomes obvious. And using a pi of 3.

Penny