A leap year contains one extra day which is added at the end
of February as February 29. It takes the Earth
365.242190 days to make a complete revolution around
the sun. The extra .242190 days is rounded up to .25
days a year or one full day every four years. The extra
day is added to synchronize
the year with the seasons. Because the .25 days overcorrects
for the actual .242190 days there is occasionally a fourth
year that not a leap year. There is a formula to determine
if a year will be a Leap Year. The rules are:
1. Every year divisible by four is a leap year.
2. But, every year divisible by 100 is NOT a leap year.
3. Unless, the year is also divisible by 400, then it is still a leap year.
Based upon this formula the year 2000 was a leap year even though it was divisible by 100. The
next year divisible by four that will not be a leap year is the year 2100.
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Databases
Enter the phrase, Leap Year into these databases: