Sorry, you need to enable JavaScript to visit this website.
Skip to main content

How Many Days Are in a Year?

Background: The true length of a year on Earth is 365.2422 days, or about 365.25 days. We keep our calendar in sync with the seasons by having most years 365 days long but making just under 1/4 of all years 366-day "leap" years. Exercise: Design a reasonable calendar for an imaginary planet. Your calendar will consist of a pattern of 366-day "leap" years and 365-day regular years that approximates your planet's average number of days per year.

Evan M. Manning
Date Accepted: 1997-09-05 Grade Group: High School (9-12) Benchmarks: M3.4.2 S17.4.1 S17.4.2 S17.4.3 Keywords: leap year year calendar error analysis fractions Microsoft Word: 04_21_97_1.docx PDF Document: 04_21_97_1.pdf