Because people like opposite day and there had to be one day to be opposite day so people picked January 25th
January 25 1981 was a Sunday.
January 25, 2020 falls on a Saturday.
January: I 25: XXV 2009: MMIX 2010: MMX
You've actually already answered your question. If you have a 25 day cycle then your period will start on day 1 and occur every 25 days!
Between January 27, 2010 and November 25, 2010 there are 302 days.
There is no such thing as opposite day! YES IT IS! OPPOSITE DAY IS ON JANUARY 25
I'm pretty sure opposite day is whenever you want opposite day to be. Perhaps if you are losing a in a fight and you tell the person your fighting with its opposite day that would work
January 25 1971 was a Monday.
25 January 1874 was a Sunday.
25 January 1943 was a Monday.
25 January 2002 was a Friday.
January 25 1955 was a Tuesday.
January 25, 1996 was a Thursday.
January 25 1981 was a Sunday.
January 25 2010 was a Monday.
January 25, 1968 was a Thursday.
January 25, 1997 was a Saturday.