365 divided by 52

Actually, there are 52 weeks of seven days plus one extra day per non-leap year. If you check consecutive non-leap years, you might notice that each date moves forward one day. This is due to the 365th day.

If there are 52 weeks each of seven days in one year, and a year is 365 days, then surely 365 over 52 must be equal to seven, right? Wrong. Besides there actually being 365.24 days in a year (See leap year for the reason) there are 51 weeks and four days in a year (five days in a leap year).