A Simple Trick For Figuring Out the Day of the Week For Any Given Date

iStock.com/Tevarak
iStock.com/Tevarak

People typically remember anniversaries in terms of dates and years, not days of the week. If you can’t remember whether you got married on a Saturday or Sunday, or don't know which day of the week you were born on, there’s a simple arithmetic-based math trick to help you figure out sans calendar, according to It's Okay To Be Smart host Joe Hanson.

Mathematician John Conway invented the so-called Doomsday Algorithm to calculate the day of the week for any date in history. It hinges on several sets of rules, including that a handful of certain dates always share the same day of the week, no matter what year it is. (Example: April 4, June 6, August 8, October 10, December 12, and the last day of February all fall on a Wednesday in 2018.) Using this day—called an “anchor day”—among other instructions, you can figure out, step by step, the very day of the week you’re searching for.

Learn more about the Doomsday Algorithm in the video below (and if it’s still stumping you, check out It’s OK to Be Smart’s handy cheat sheet here).

21 Widespread Myths About Animals, Debunked

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YouTube

No, that nasty-looking wart on your finger didn't come from a toad. And yes, giraffes really do need more than 30 minutes of shut-eye in a day. Chances are that one of the "facts" you've come to know about your favorite animal isn't a fact at all. (Cats can swim and dogs do see colors—though in a different way than you probably do.)

Since our fuzzy, furry, finned, and winged friends can't always speak for themselves, Mental Floss Editor-in-Chief Erin McCarthy is here to clear up 21 widespread animal myths. So gather up your pets and check out this week's all-new edition of the Mental Floss List Show. You can watch the full episode below.

For more episodes like this one, be sure to subscribe here.

17 Signs That You’d Qualify as a Witch in the 1600s

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YouTube

Are you a woman? Do you have a birthmark? Do you enjoy spending quality time with friends without a chaperone? You might just be a witch! At least that's how the thinking went in the 1600s, when now completely normal behaviors could have seen you accused of witchcraft.

Grab your broom and the pointiest black hat you can find, and join Mental Floss editor-in-chief Erin McCarthy as she shares 17 signs that might have branded you a witch during the 17th century in this week's all-new edition of the Mental Floss List Show. You can check out the full episode below:

For more episodes like this one, be sure to subscribe here!

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