Calculating how many days in a revolution (year).
- 365x4=1,460 (four years)
- 1,460+1=1,461 (including extra day for leap year)
- 1,461x25=36,525 (there are 25 four-year cycles every century)
- 36,525-1=36,524 (the 100th year does not have an extra day unlike most 4th years)
- 36,524x4=146,096 (400 years)
- 146,096+1=146,097 (400th year, however, is a leap year)
- 146,097/400=365.2425 (the actual number of days in a year if there are 24 hours a day)
Calculating how many rotations in a year:
- There are 24 hours in a day, but the Earth takes 23 hours, 56 minutes, and 4 seconds to make a full rotation.
- 24x60x60=86,400 (number of seconds in a day)
- 23x60x60+56x60+4=86,164 (number of seconds in a rotation period)
- 86,164/60=23.93444... (number of hours in a rotation in decimal form)
- 365.2425*24=8,765.82 (number of hours in an actual year)
- 8,765.82/23.93444=366.2428856599044 (number of rotations in a revolution)