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Dr. Shapiro's Puzzle of the Day

Today's Puzzle

Thursday, May 27
1.       2.       3.       4.       5.       6.       7.      

Can you identify seven eight U. S. states from close-ups of their state quarters and license plates? (Each of #1–6 has a single answer, but the quarter and license plate in #7 are from different states, despite depicting the same object.)

   


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Yesterday's Puzzle + Solution

Banana is a count noun: you can say "a banana", "three bananas", "too many bananas", and so on. Rice is a mass noun: you can say "a cup of rice", "three grains of rice", or "too much rice", but you can't say "a rice" or "three rices". (Well, you can, but people will give you a certain look.)

Sometimes mass nouns masquerade as count nouns. Peas were once pease, a mass noun like rice (as in "pease porridge hot, pease porridge cold"). It wasn't a plural, and there wasn't a singular form; when toddlers said "I eated a pea", their parents probably laughed at their double mistake. But over time, the obvious logic of peas/pea won out and a count noun was born.

But there's another common foodstuff which is still a mass noun today, despite looking like a plural. If you encounter this word without its final -s, it's almost certainly as an adjective (perhaps before milk or bread). What is it?

BONUS: Can you think of any other nouns that look like plurals but don't have singular forms?

Solution The answer is oats.

Now, you may feel that a single kernel or flake of oats is "an oat", and I'm not here to tell you you're wrong! There was no definitive moment when pease gave way to pea, and a lot of people probably used pea before it became universally accepted as standard. Oats is likely on a similar journey. But for now, the vast majority of usage treats oats either as a mass noun or as an adjective (oat milk, oat bread, oat clusters, oatmeal).

I received these answers to the bonus question: scissors, pants, mathematics.

My uncle once tried to be funny by saying "Pass me the scissor! My pant has a hole!"
I stared at him until he realized how nonsensical that request truly was, then we BOTH cracked up.

Congratulations to yesterday's solvers Anna K., Kate, and the Greggs. 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 2020 to March 2021.