Leap Year

Every year is actually 365 and 1/4 days long. So every 4 years they have to add another day so that everything stays in sync. So, every February, they add a an extra day, every 4 years, so that February has 29 days in Leap years and 28 in common years.

Between 1933 and 2015, there have been 20 leap years. They were 1936, 1940, 1944, 1948, 1952, 1956, 1960, 1964, 1968, 1972, 1976, 1980, 1984, 1988, 1992, 1996, 2000, 2004, 2008 and 2012. The next will be in 2016.

Because it does not divide evenly by 4.

Because it does not divide evenly by 4.

Because it does not divide evenly by 4.

Because it does not divide evenly by 4.

Because it does not divide evenly by 4.

Because it does not divide evenly by 4.

Because it does not divide evenly by 4.

Because it does not divide evenly by 4.

Because it does not divide evenly by 4.

Because it does not divide evenly by 4.

Because it does not divide evenly by 4.

No, it was not. We often thing that all years that are multiples of 4 are leap years, but there are two exceptions to the general rule.

1. Century years - year numbers divisible by 100 - are NOT leap years, except....

2. Years that are evenly divisible by 400, such as 1600, 2000, and 2400, ARE leap years.

If the Earth took exactly 365 days to go around the Sun, there would be no need for leap years. If the Earth took exactly 365.25 years to go around the Sun, then we would still need Exception #1.

But the Earth actually takes 365.26 days to go around the Sun, so we need both exception rules.

Skipping a Tuesday is basically the same as asking when was Christmas Day on a Wednesday in a leap year. That happens every 28 years. Going from the start of the 20th century to 2014, that happened in 1912, 1940, 1968 and 1996. It will next happen in 2024.

The year MUST start on a Sunday. For a leap year, it can start on Saturday or Sunday.

In any period of 400 years there are 303 non-leap years, of which 43 begins and ends with a Sunday, and there are 97 leap years, of which 28 begins with a Saturday or a Sunday.

So the probability in a non-leap year is 43/303, or 14.2%.

And the probability in a leap year is 28/97, or 28.9%

No, it's not currently on the agenda.

The real, or astronomical, year has a length of a little less than 365.25 days. To have a full number of days in a year, the length of the year is usually set at 365, and every 4 years, an extra day is added. Thus, on average, the length of the calendar year matches the astronomical year; an important astronomical event like the Spring equinox (for the Northern Hemisphere) will maintain its date - approximately - at March 20 or 21.

The real, or astronomical, year has a length of a little less than 365.25 days. To have a full number of days in a year, the length of the year is usually set at 365, and every 4 years, an extra day is added. Thus, on average, the length of the calendar year matches the astronomical year; an important astronomical event like the Spring equinox (for the Northern Hemisphere) will maintain its date - approximately - at March 20 or 21.

The real, or astronomical, year has a length of a little less than 365.25 days. To have a full number of days in a year, the length of the year is usually set at 365, and every 4 years, an extra day is added. Thus, on average, the length of the calendar year matches the astronomical year; an important astronomical event like the Spring equinox (for the Northern Hemisphere) will maintain its date - approximately - at March 20 or 21.

The real, or astronomical, year has a length of a little less than 365.25 days. To have a full number of days in a year, the length of the year is usually set at 365, and every 4 years, an extra day is added. Thus, on average, the length of the calendar year matches the astronomical year; an important astronomical event like the Spring equinox (for the Northern Hemisphere) will maintain its date - approximately - at March 20 or 21.

A leap year is 52 weeks plus 2 days. That means that 2 days have 53 instances. So there is a 2/7 chance that there will be 53 Fridays. There is absolutely no chance that there are 54 Sundays, since 53 is the most you can have.

Good luck.

The exact probability is 28/97, which is about 28.87%.

The Greeks noticed that eight solar years was close to 99 lunar months. So they started a calendar called the octaeteris, which was eight solar years or 99 lunar months. Later, they measured the octaeteris as two four-year periods, one of 49 months and one of 50 months, and they called these 4-year periods "Olympiads." This 4-year period still survives today. Every four years, we add a leap day in February, and we also hold the Olympics. In America, we even elect a President (a "new king") every four years.

The Olympics originated as a reenactment of an astronomical myth which described a calendar. The story tells of a man named Pelops who wanted to marry Hippodamia, the daughter of King Oenomaus. Oenomaus was willing to offer his daughter's hand to any potential suitor who could compete with him and win in a chariot race. Each contestant would take Hippodamia in his chariot and try to beat her father, but Oenomaus would always win and then kill the losing suitor. Before Pelops came along, Oenomaus had so far killed twelve suitors and hung up their heads for display. Hippodamia loved Pelops, and she secretly fixed her father's chariot so it would fail. In the race, his chariot crashed and Oenomaus died, making him the 13th victim, so Pelops won. Pelops got the girl, became the new king, and according to Pindar (5th c. BC), the Olympics were started to commemorate the chariot race of Pelops.

There is another myth that relates the origin of the Olympic games and involves Herakles, who was recognized as a Sun-god. Many of his Twelve Labors correspond to the 12 signs of the Zodiac, such as the slaying the Nemean lion (Leo), capturing the Cretan bull (Taurus), etc. One of the Twelve Labors imposed on Herakles was to clean the cattle stables of King Augeas of Elis, a city-state located about 30 miles from Olympia. He accomplished his task in one day by diverting the Alpheios River from its course and causing it to flow through the stables. According to this myth, Herakles celebrated his success by founding the Olympian games. Historically speaking, Elis was in actuality the city-state that supervised the Olympic games, and the peak of the Olympic festival occurred when one hundred oxen were sacrificed to Zeus.

Anyway, it's all about mythology... The Greeks noticed that eight solar years was close to 99 lunar months. So they started a calendar called the octaeteris, which was eight solar years or 99 lunar months. Later, they measured the octaeteris as two four-year periods, one of 49 months and one of 50 months, and they called these 4-year periods "Olympiads." This 4-year period still survives today. Every four years, we add a leap day in February, and we also hold the Olympics. In America, we even elect a President (a "new king") every four years.

The Olympics originated as a reenactment of an astronomical myth which described a calendar. The story tells of a man named Pelops who wanted to marry Hippodamia, the daughter of King Oenomaus. Oenomaus was willing to offer his daughter's hand to any potential suitor who could compete with him and win in a chariot race. Each contestant would take Hippodamia in his chariot and try to beat her father, but Oenomaus would always win and then kill the losing suitor. Before Pelops came along, Oenomaus had so far killed twelve suitors and hung up their heads for display. Hippodamia loved Pelops, and she secretly fixed her father's chariot so it would fail. In the race, his chariot crashed and Oenomaus died, making him the 13th victim, so Pelops won. Pelops got the girl, became the new king, and according to Pindar (5th c. BC), the Olympics were started to commemorate the chariot race of Pelops.

There is another myth that relates the origin of the Olympic games and involves Herakles, who was recognized as a Sun-god. Many of his Twelve Labors correspond to the 12 signs of the Zodiac, such as the slaying the Nemean lion (Leo), capturing the Cretan bull (Taurus), etc. One of the Twelve Labors imposed on Herakles was to clean the cattle stables of King Augeas of Elis, a city-state located about 30 miles from Olympia. He accomplished his task in one day by diverting the Alpheios River from its course and causing it to flow through the stables. According to this myth, Herakles celebrated his success by founding the Olympian games. Historically speaking, Elis was in actuality the city-state that supervised the Olympic games, and the peak of the Olympic festival occurred when one hundred oxen were sacrificed to Zeus.

Anyway, it's all about mythology...

The same as in a leap year - 30 days. This might help :-

30 days have September, April ,June and November,

All the rest have 31

Excepting February alone, which has 28 days clear,

And 29 in each Leap Year

US presidential elections (first Tuesday in November).

It was really ever 'invented'. There actually aren't 365 days in a year. There are 365 and one fourth. That's why every four years an extra day is added. The extra fourth has to go somewhere. Hope this helped.

I first answered this question in August 2010. It is now January 2018, so I'll update it:

Not sure if you're wanting 1980 included or not since it was a leap year.

Leap years are those years which are divisible by 4 EXCEPT for centuries when the century must be divisible by 400; they occur every four years (except possible when a century ends).

2000 IS divisible by 400 so it was a leap year.

As 1980 was a leap year, by subtracting 1980 from the current year, dividing by 4 and ignoring any remainder, the number of leap years after 1980 is found.

(2018 - 1980) ÷ 4 = 38 ÷ 4 = 9 r 2 → 9 leap years after 1980

Including 1980 there have been 10 leap years: 1980, 1984, 1988, 1992, 1996, 2000, 2004, 2008, 2012, 2016

Excluding 1980, the first leap year after 1980 was 1984 there have been 9.

The next leap years will be 2020, 2024, 2028, 2032, ...

These are the years of the Summer Olympic games.

No ! The presidential elections are not always on a leap year. Even though a leap year is every 4 years, not every election is a leap year. The notable exceptions are years that mark centuries (example 1800, 1900, 2000). If those years are not divisible by 400, then the year is not a leap year.

There are traditions that a woman can ask a man to marry her in a leap year on St. Valentine's Day and on the 29th of February.

There are lots, but the main two would be the Summer Olympic Games and the European Soccer Championships.

As of 2015, there have been 19 leap years since 1939. They were 1940, 1944, 1948, 1952, 1956, 1960, 1964, 1968, 1972, 1976, 1980, 1984, 1988, 1992, 1996, 2000, 2004, 2008 and 2012. The next one will be 2016.

If you are born on February 29th, your birthday is February 29th. 40 years later, you will be 40 years old, but your birthday will have only come around 10 times. This is why most people born on February 29th celebrate their birthday on either February 28th or March 1st.

Leap year comes around whenever people say it does.
It's a human invention, just like the rest of the calendar.

The system works like this:

Every fourth year is a leap year ... same year as the Summer Olympics and the US presidential election.
Those are the years that can be evenly divided by 4.

EXCEPTIONS:
The last year of each Century can be evenly divided by 4, but is NOT a leap year.
Examples are 1800, 1900, 2000, 2100, etc.

There is a pattern in the way days and dates fall. If Christmas Day is on a Sunday 3 years before a leap year, then it will always follow that the Christmas Days in the next years are a Monday, a Tuesday, and for the leap year Wednesday will be skipped and Christmas Day will be on a Thursday. Follow on for another 3 years and you get Friday, Saturday and Sunday. Leap years are always even, so if it is 3 years before a leap year, then the first year that the Sunday is on has to be odd, as will the year 3 years after a leap year. These patterns are common and you could look at other specific combinations of dates and days in the same way and find recurring patterns there too.

The song is "Just Say Yes" by Snow Patrol.