### Did you know that ...

... there is a big difference between mass and weight ? more

## The exact duration of one year

*The duration of one year is 365 days and a quarter.*

The exact duration of one year is 365 days, 5 hours, 48 minutes and 46 seconds. In summary, it is as 365 days and a quarter (in fact they would be 365 days and 6h). For this reason, every four years we have a leap year, of 366 days.

Also, to correct the inaccuracy of 365 days and a quarter, some years that should be leap are not it. The rule to know if one year is leap or not is the following one:

One year is leap if it is divisible for 4, except those divisible for 100 but not for 400.

Therefore, 1900 would not be leap but the 2000 would be it. On the other hand, the 2100 neither would be it.

Posted by Turrente