There were 25 leap years in the 20th century. They were:
1904
1908
1912
1916
1920
1924
1928
1932
1936
1940
1944
1948
1952
1956
1960
1964
1968
1972
1976
1980
1984
1988
1992
1996
2000
The first leap year of the twentieth century (1901 - 2000) was 1904. The final year of the nineteenth century (1900) was not a leap year, as any century year needs to be divisible not only by 4, but also by 400.
24
- as if a year is divisible by 100 it is not a leap year.
Neither 1900 nor 2000 were leap years
- something to do with not exactly 4 years still makes calculations correct.
So 100 - 4 = 96
96 / 4 = 24
25 cause a leap year occurs every 4 years
20 years is less than a century. A century is 100 years. So 20 years is one fifth of or 20% of a century.
20 leap years.
There are around 7304.8 days in 20 years. This takes into account that there are approximately 5 leap years.
All years divisible by 4 are leap years: 1956, 1960, etc. (add 4 at a time).
There were 20 leap years from 1929 through 2008. (the next one is 2012):19321936194019441948195219561960196419681972197619801984198819921996200020042008
175320 Hours counting leap yrs. 24 hrs in a day 365 days in a yr multiply by 20 add leap yrs (24x5=120) 175200 hours excluding leap years
20. Divide 80 by 4. I hope this helped! :)
That would be 2 years, 20 days (19 if a leap year is involved)
Depending on the number of leap years in the period (19 or 20), it is 2524521600 or 2524608000 seconds, plus any leap seconds.
what years were covered by the 20 century
80 years = 2,524,651,960 secondsUsing: 1 year = 365.25636 days