Question

why do we need to have a leap year once every four years??​

Answer 1

Answer:

Every four years, we add an extra day, February 29, to our calendars. These extra days – called leap days – help synchronize our human-created calendars with Earth's orbit around the sun and the actual passing of the seasons. ... It'd be off by about 25 days after 100 years

Answer 2

*Question:-

why do we need to have a leap year once every four years??

*Answer:-

Nearly every four years, we add an extra day to the calendar in the form of February 29, also known as Leap Day. Put simply, these additional 24 hours are built into the calendar to ensure that it stays in line with the Earth's movement around the Sun.