Every year has more than 5 Fridays, 5 Saturdays and 5 Sundays.
About twice each year
According to my desktop calendar, July will have five Fridays and Saturdays (and even some Thursdays) in 2016, 2021, 2022, 2027,2032, 2033, etc... If you look at http://www.timeanddate.com/calendar/monthly.html?year=2021&month=7&country=1 you will see that 2021, 2027, 2032 do not have 5 Sundays. The other years 2016, 2022, 2033 do have 5 Fridays, Saturdays, and Sundays. You are little confused since your first parahraph discusses Fridays and Saturdays, in which case 2021 and 2022 do indead have 5 Fridays and 5 Saturdays in July. In paragraph two above, you begin talking about Sundays and which years in which July will 5 each of Fridays, Saturdays and Sundays. Every month with 31 days will have 5 instances of the first 3 days in the month. This will repeat in a 5-6-5-11 year cycle and then repeat. So it should be 2016, 2022, 2033, 2039, 2044, 2050, 2056 - don't forget to consider leap year which will cause a 1 day shift.
52 Saturdays and 53 Sundays.52 Saturdays and 53 Sundays.52 Saturdays and 53 Sundays.52 Saturdays and 53 Sundays.52 Saturdays and 53 Sundays.52 Saturdays and 53 Sundays.52 Saturdays and 53 Sundays.52 Saturdays and 53 Sundays.52 Saturdays and 53 Sundays.52 Saturdays and 53 Sundays.52 Saturdays and 53 Sundays.
There were exactly 53 Fridays and 52 Saturdays in the year 2010.
There are 14 calendar variations (7 days of the week plus leap years). Some years October will have 5 Fridays, 5 Saturdays, and 5 Sundays. October 1999, 2010, 2021, and 2032 all have 5 Fridays, 5 Saturdays, and 5 Sundays. This looks like an 11 year gap, but October 1988 and 2043 do not have 5 weekends.
More like every 28 years, I think.
That depends on the year. There are always at least 52 Saturdays and 52 Sundays in a year, so most years there are 104 in total. Some years there can be 53 Sundays and 52 Saturdays, in which case the total is 105. There can also be 52 Sundays and 53 Saturdays, again giving a total of 105. If a leap year starts on a Saturday, then there are 53 Saturdays and 53 Sundays, so there are 106 in total.
Prior to this year, July had five Fridays and five Saturdays in 2010.
This happens on average of once every 7 years- 4 times in every 28-year cycle of the calendar. It happens whenever March first is a Friday..
2011, 2016 (leap year), 2022, 2033, 2039, 2044 (leap year), 2050, 2061, 2067, 2072 (leap year), 2078, 2089, 2095, 2101, 2107, 2112 (leap year), 2118, 2129
Exactly 14.25% of all Augusts have five each of Fridays, Saturdays and Sundays. It happens exactly 57 times in any 400-year period. That means that the average frequency is about every 7.02 years.
210