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Dr. Shapiro's Puzzle of the Day

Today's Puzzle

Friday, January 22

I was recently reminded of the delicious animated short film in which these images appear. What snack is being made in this film?

   


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Yesterday's Puzzle + Solution

When I do laundry in the evening, I leave the light on in the laundry room so I'll remember to move the clothes to the dryer and to hang and fold them when they're done.

This system has some flaws in a multi-person household. My wife would turn off the light, thinking she had turned it on—or she'd leave it on, thinking I had turned it on when I hadn't. Communication is hard!

But my wife loves making systems, so she hung a card by the light switch that I could flip over to signal that the light was lit on purpose. She labeled the sides of this card in a non-straightforward (yet curiously logical) manner, using two rubber stamps from my voluminous collection. Which two, and which means what?

Hint No. 5 isn't one of them. That's just bait.

Solution No. 4 means the light isn't meant to be on (so if you're able to read the card, please correct the situation). No. 6 means it is meant to be on (good work for leaving it on).

Most of the wrong guesses revolved around No. 7, though everyone had a different reason.

Congratulations to yesterday's solvers... well, solver. Several people got half the answer but only 🎉 Peter M. 🎉 got it all. Thanks to everybody who made a guess!

About This Site

Though he now teaches mathematics, Dr. (né Mr.) Shapiro's first job in a K–12 school was as a lunch monitor in Davis, CA. It was there that he originated the Puzzle of the Day, even rewarding correct answers with tickets in denominations like "15 points" (though without a clear idea of how he'd ultimately redeem these). Dr. Shapiro's favorite puzzle from this pre-professional era was "Tell me the location of the beehive on this campus."

Ten years later, Dr. Shapiro revived Puzzle of the Day at Proof School, writing each day's puzzle on a name tag. After 600 puzzles or so, he was just starting to feel normal about students reading his chest all the time when campus closed and the puzzle, like the rest of our lives, moved online. New puzzles are posted daily on school days.

Want to catch up on old PotDs? There's an archive currently containing puzzles from March to December 2020.