“Mama, I wonder why pizzas are circles and the boxes are squares but the pieces are triangles,” asked the earnest 5-year-old.

I have to give a shout out to Soho Pizza in Montclair. This pie was half cheese and half Prince Street – which is mushroom, eggplant, zucchini, and cheese. So good!

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Adjusting to the car culture, dealing with leaving a career I love, and spouting off along the way.

Smart kid and that pizza looks fantastic! I like artichoke hearts on mine.

It was so good!

That’s a great question!

Agreed! I had never thought of it as a geometry problem.

You know how I love pizza. That looks delicious!! Excellent questions , btw. I’d like to know your answers.

I don’ think “Because that’s how God made them” works in this instance. Maybe “The Man”?

looks delish.. no matter what the shape!

It was! Mmmmmm.

That looks so good. Seriously.

I just had the leftover for lunch. Two days in a row is not enough.

Hi row-mie, I want to eat pizza now. It look so delicious, yummmm

Strongly suggested! Can’t wait to check out my row-mates later today!

See if your 5-year old likes this: start with a pizza cut up into six equal slices, and with her spot-on observation that each piece is (almost) a triangle. If you cut off the edge of the crust to make each slice a true triangle, then those triangles have all sides the same length (try it and see). Now put the slices back together to make a pizza hexagon. That hexagon is two triangle-lengths across (between opposite vertices), and six triangle-lengths all the way around — i.e., three times as far around as it is across. The original pizza is exactly as far across as the hexagon is, and a little further around — in other words, a bit more than three times as far around as it is across.

And when she asks you what you call that, tell her: PIzza Pi!

square peg round hole…round peg square box. It’s like a DaVinci guy in the circle, arms stretched out to touch all sides of the circle.

Wow! WOW! I need to take a minute to close my eyes and envision this comment.

A (good) picture’s worth a thousand words. Here’s one I found online, with the circular pizza, and the square box, and the triangular slices:

The pizza is two triangle-lengths across. The hexagon inside is six triangle-lengths around (three times the diameter of the circle), and the box outside is eight triangle-lengths around (four times the diameter of the circle). So the circle is between three and four times as far around as it is across (i.e., pi is between three and four), and a lot closer to three than four.

Not that I’m trying to turn this into a math blog or anything…

By the way, having seen the 5-year old’s drawings, I’m not the least bit surprised that she thinks in terms of shapes!

Oops, didn’t manage to make link to the picture work correctly. It’s here: http://www.nilesjohnson.net/teaching/pi_approx.png