there 5 sundays,mondays,saturdays in every 200 years
That can only happen when December starts on a Sunday. That happens every 5, 6 or 11 years. In the past 50 years it happened in: 1968 1974 1985 1991 1996 2002 2013 The next time will be in 2019, 6 years after 2013.
Exactly 14.25% of all July 23rds are Wednesdays. 14% are Sundays, 14.5% are Mondays, 14.25% are Tuesdays, 14.25% are Wednesdays, 14.5% are Thursdays, 14% are Fridays, and 14.5% are Saturdays.
The odds are exactly 14.5%, which makes the average frequency once per 6.9 years.
Every 5, 6, or 11 years, depending on how the leap years fall. August had this configuration in 1982, 1993, 1999, 2004, and 2010. Next three times will be in 2021, 2027 and 2032.
4 years
Never.
October 2011, December 2012, March 2014 for starters. In other words, how often does a 31-day month begin on a Saturday? Fairly often.
Whenever December begins on a Saturday, which happens 4 times every 28 years, in a 6-5-6-11 pattern. December had this calendar in 1984, 1990, 2001 and 2007, and it will recur in 2012, 2018 and 2029.
Over the very long average, once for every seven years. And it's "often".
Exactly 14% of all Decembers have five of each of Fridays, Saturdays and Sundays.
Sitting (meeting) hours of the House of Commons2.30-10.30pm on Mondays and Tuesdays, 11.30am-7.30pm on Wednesdays, 10.30am-6.30pm on Thursdays and 9.30am-3pm on sitting Fridays. Sitting (meeting) hours for Westminster Hall debates9.30am-2pm on Tuesdays, 9.30-11.30am and 2.30-5pm on Wednesdays and 2.30-5.30pm on Thursdays.