How Special Is Your Birthday? (Mathematically Speaking, That Is)

Sure, your birthday is your important day, but it's not only yours. What are the chances of two people in a group sharing a birthday? It's actually a lot more likely than you think.

In the video above, Joe Hanson from It’s Okay To Be Smart celebrates the program's third birthday by diving into the probability of shared birthdays. How crazy is it that out of 44 presidents, James K. Polk and Warren G. Harding share a November 2 birthday? Not crazy at all: In a group of 44 people, there’s a 93 percent chance that two of them will have been born on the same day.

That stat seems pretty remarkable, but as Hanson says, it’s because “our brains are bad at figuring out the power of chance.” Check out the video for more dizzying data on the probability of shared birthdays, and for a good explanation of why the numbers work out that way. Plus, the reason why the frequency of Facebook birthdays hits a milestone at about the 2153 friend mark.

Banner image via YouTube.

© 2017 USPS
Pop Culture
Speedy Delivery: Mister Rogers Will Get His Own Stamp in 2018
© 2017 USPS
© 2017 USPS

USPS 2018 Mister Rogers stamp
© 2017 USPS

After weeks of mailing out this year’s holiday cards, postage might be the last thing you want to think about. But the U.S. Postal Service has just given us a sneak peek at the many iconic people, places, and things that will be commemorated with their own stamps in 2018, and one in particular has us excited to send out a few birthday cards: Mister Rogers.

In celebration of the 50th anniversary of Mister Rogers’ Neighborhood, Fred Rogers’s groundbreaking PBS series that the USPS says “inspired and educated young viewers with warmth, sensitivity, and honesty,” the mail service shared a mockup of what the final stamp may look like. On it, Rogers—decked out in one of his trademark colorful cardigans (all of which were hand-knitted by his mom, by the way)—smiles for the camera alongside King Friday XIII, ruler of the Neighborhood of Make-Believe.

Though no official release date for Fred’s forever stamp has been given, Mister Rogers is just one of many legendary figures whose visages will grace a piece of postage in 2018. Singer/activist Lena Horne will be the 41st figure to appear as part of the USPS’s Black Heritage series, while former Beatle John Lennon will be the face of the newest Music Icons collection. Sally Ride, the first American woman in space, will also be honored.

Can You Spot the Christmas Pudding?

Whether it’s a sheep hanging out with Santa Claus or a panda bear hiding among some snowmen, regular Mental Floss readers know that hidden picture brainteasers are one of our favorite things. And the optical experts at have released a delicious one, just in time for Christmas. Somewhere in the midst of all these holiday-themed goodies above, there’s a holiday pudding just waiting to be discovered. Can you spot it? Your time starts … now.

If you give up, or are the kind of person who reads the last page of a book before the first one and just wants to know the answer, scroll down to see where it’s hiding.



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