The number pi has fascinated mathematicians for millennia. You know you memorized equations with pi in high school â€¦ but what does it all mean? Also, is it just me, or does all this talk kind of make you want to eat some pie?

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Question 1 of 9

OK. You know pi is 3.14. But â€¦what is it?

the height of a pyramid times the lenght of its longest side

the circumference of a circle divided by its diameter

the diameter of a circle divided by its radius

the area of the base of a pyramid

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Pi is a constant: the ratio of a circleâ€™s circumference to its diameter. No matter what circle you choose, its circumference is always a little more than three times as long as its diameter.

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Question 2 of 9

Pi (Ï€) is the first letter in the Greek word Ï€ÎµÏÎ¹Î¼ÎµÏ„ÏÎ¿Ï‚. What does that word mean?

circle

radius

perimeter

wheel

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Perimeter. Greek vocabulary word of the day!

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Question 3 of 9

Pi is an irrational number. What does that mean?

It has more than 10 digits after the decimal point

It believes those urband legend emeails. And forwards them. An-noy-ing

It can't be expressed as a fraction of two integers

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You can't divide one integer by another and get pi. It's really close to 355/113 â€¦ but it's not exactly 355/113. A mathematician proved that pi is irrational in 1768.

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Question 4 of 9

Which of the following people is not a mathematician who calculated a new value of pi?

Archimedes

Ptolemy

Zu Chongzhi

Judy Garland

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Judy Garland. A list of people who've come up with a better approximation of pi is like a who's who of mathematicians. Pi is, apparently, totally fascinating.

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Question 5 of 9

How many digits of pi have been calculated?

556

69,890

just under a million

more than a trillion

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More than a trillion. The Guinness record for reciting pi from memory is 67,890. Someone else claims to have recited 100,000 digits. Yipe.

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Question 6 of 9

Pi is not only irrational, but also transcendental. What the heck does that mean?

It practices meditation daily

It is not the solution to an algebraic equation

It has no application in daily life

It can be found by dividing one integer by another

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There's no nice clean algebraic equation you can write for pi. Like xÂ²-2=0, for example. It just can't be done. Pi is a wacky number. Transcendental, in fact. By "nice clean" we mean "polynomial with integer coefficients."

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Question 7 of 9

According to the American Pie Council, when is National Pie Day?

January 23rd

March 14th

July 4th

Thanksgiving

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Jan. 23. Isn't that weird? Every nerd knows you eat pie on March 14. (3/14 â€“ get it?) But thatâ€™s cool. Iâ€™d eat pie every day. You hear that, American Pie Council? I LOVE PIE.

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Question 8 of 9

What are pie weights for?

Losing the weight you gain from eating pie

Holding down the bottom of a pie crust when you bake it without a filling in it

Making a pie too heavy for a thief to steal it from the windowsill

holding a double-crusted pie together in the oven

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If youâ€™re making a pie crust that is baked before filling, you can keep it from buckling by weighting it with pie weights.

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Question 9 of 9

Enough fun. Time for more math. (Kidding! Math is fun!) Whatâ€™s the formula for the volume of a sphere?

4/3 Î r3

4Î r3

Î r2

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Itâ€™s 4/3 Ï€ rÂ³ . Sorry, Mr. Walstein, I know you taught me this in ninth-grade geometry, but I had to look it up to write the quiz.

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